diff --git a/01-rstudio-intro.html b/01-rstudio-intro.html
index 31690293b..5363bbd4f 100644
--- a/01-rstudio-intro.html
+++ b/01-rstudio-intro.html
@@ -1436,7 +1436,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/01-rstudio-intro.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/02-project-intro.html b/02-project-intro.html
index f60d38748..97e94e672 100644
--- a/02-project-intro.html
+++ b/02-project-intro.html
@@ -589,7 +589,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>By running these commands in the shell:</p>
 <div class="codewrapper sourceCode" id="cb1">
@@ -787,7 +787,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/02-project-intro.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/03-seeking-help.html b/03-seeking-help.html
index c0c1b21a6..c968c2916 100644
--- a/03-seeking-help.html
+++ b/03-seeking-help.html
@@ -822,7 +822,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/03-seeking-help.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/04-data-structures-part1.html b/04-data-structures-part1.html
index 4d0d9053a..17ef39dde 100644
--- a/04-data-structures-part1.html
+++ b/04-data-structures-part1.html
@@ -816,7 +816,7 @@ <h3 class="callout-title">Discussion 1<a class="anchor" aria-label="anchor" href
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Discussion 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>By keeping everything in a column the same, we allow ourselves to
 make simple assumptions about our data; if you can interpret one entry
@@ -1041,7 +1041,7 @@ <h4 id="print-the-data">1. Print the data<a class="anchor" aria-label="anchor" h
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Tip 1.1</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>Show the content of any variable by typing its name.</p>
 <div class="section level3">
@@ -1073,7 +1073,7 @@ <h3 class="callout-title">2. Overview of the data types<a class="anchor" aria-la
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Tip 1.2</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>In the chapter “Data types” we saw two functions that can show data
 types. One printed just a single word, the data type name. The other
@@ -1112,7 +1112,7 @@ <h4 id="which-data-type-do-we-need">3. Which data type do we need?<a class="anch
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Tip 1.3</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>Scroll up to the section about the <a href="#the-type-hierarchy">type
 hierarchy</a> to review the available data types</p>
@@ -1125,7 +1125,7 @@ <h4 class="accordion-header" id="headingSolution4">Tip 1.3</h4>
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution to Challenge 1.3</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ul><li>Weight is expressed on a continuous scale (real numbers). The R data
 type for this is “double” (also known as “numeric”).</li>
@@ -1157,7 +1157,7 @@ <h3 class="callout-title">4. Correct the problematic value<a class="anchor" aria
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Tip 1.4</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>Revisit the hierarchy of data types when two different data types are
 combined.</p>
@@ -1195,7 +1195,7 @@ <h4 id="convert-the-column-weight-to-the-correct-data-type">5. Convert the colum
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Tip 1.5</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The functions to convert data types start with <code>as.</code>. You
 can look for the function further up in the manuscript or use the
@@ -1385,7 +1385,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Solution to Challenge 2</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb92">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1609,7 +1609,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution9" aria-expanded="false" aria-controls="collapseSolution9">
   <h4 class="accordion-header" id="headingSolution9">Solution to Challenge 3</h4>
 </button>
-<div id="collapseSolution9" class="accordion-collapse collapse" data-bs-parent="#accordionSolution9" aria-labelledby="headingSolution9">
+<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
 <div class="accordion-body">
 <p>You get the names of an object by wrapping the object name inside
 <code>names(...)</code>. Similarly, you get the data type of the names
@@ -1652,7 +1652,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution10" aria-expanded="false" aria-controls="collapseSolution10">
   <h4 class="accordion-header" id="headingSolution10">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
 <div class="accordion-body">
 <pre><code><span><span class="va">letter_no</span> <span class="op">&lt;-</span> <span class="fl">1</span><span class="op">:</span><span class="fl">26</span>   <span class="co"># or seq(1,26)</span></span>
 <span><span class="fu">names</span><span class="op">(</span><span class="va">letter_no</span><span class="op">)</span> <span class="op">&lt;-</span> <span class="va">LETTERS</span></span>
@@ -1840,7 +1840,7 @@ <h3 class="callout-title">Challenge 5<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution11" aria-expanded="false" aria-controls="collapseSolution11">
   <h4 class="accordion-header" id="headingSolution11">Solution to Challenge 5</h4>
 </button>
-<div id="collapseSolution11" class="accordion-collapse collapse" data-bs-parent="#accordionSolution11" aria-labelledby="headingSolution11">
+<div id="collapseSolution11" class="accordion-collapse collapse" aria-labelledby="headingSolution11" data-bs-parent="#accordionSolution11">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb138">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2100,7 +2100,7 @@ <h3 class="callout-title">Challenge 6<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution12" aria-expanded="false" aria-controls="collapseSolution12">
   <h4 class="accordion-header" id="headingSolution12">Solution to Challenge 6</h4>
 </button>
-<div id="collapseSolution12" class="accordion-collapse collapse" data-bs-parent="#accordionSolution12" aria-labelledby="headingSolution12">
+<div id="collapseSolution12" class="accordion-collapse collapse" aria-labelledby="headingSolution12" data-bs-parent="#accordionSolution12">
 <div class="accordion-body">
 <p>What do you think will be the result of
 <code>length(matrix_example)</code>?</p>
@@ -2144,7 +2144,7 @@ <h3 class="callout-title">Challenge 7<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution13" aria-expanded="false" aria-controls="collapseSolution13">
   <h4 class="accordion-header" id="headingSolution13">Solution to Challenge 7</h4>
 </button>
-<div id="collapseSolution13" class="accordion-collapse collapse" data-bs-parent="#accordionSolution13" aria-labelledby="headingSolution13">
+<div id="collapseSolution13" class="accordion-collapse collapse" aria-labelledby="headingSolution13" data-bs-parent="#accordionSolution13">
 <div class="accordion-body">
 <p>Make another matrix, this time containing the numbers 1:50, with 5
 columns and 10 rows. Did the <code>matrix</code> function fill your
@@ -2184,7 +2184,7 @@ <h3 class="callout-title">Challenge 8<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution14" aria-expanded="false" aria-controls="collapseSolution14">
   <h4 class="accordion-header" id="headingSolution14">Solution to Challenge 8</h4>
 </button>
-<div id="collapseSolution14" class="accordion-collapse collapse" data-bs-parent="#accordionSolution14" aria-labelledby="headingSolution14">
+<div id="collapseSolution14" class="accordion-collapse collapse" aria-labelledby="headingSolution14" data-bs-parent="#accordionSolution14">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb173">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2234,7 +2234,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution15" aria-expanded="false" aria-controls="collapseSolution15">
   <h4 class="accordion-header" id="headingSolution15">Solution to Challenge 9</h4>
 </button>
-<div id="collapseSolution15" class="accordion-collapse collapse" data-bs-parent="#accordionSolution15" aria-labelledby="headingSolution15">
+<div id="collapseSolution15" class="accordion-collapse collapse" aria-labelledby="headingSolution15" data-bs-parent="#accordionSolution15">
 <div class="accordion-body">
 <p>Consider the R output of the matrix below:</p>
 <div class="codewrapper">
@@ -2334,7 +2334,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/04-data-structures-part1.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/05-data-structures-part2.html b/05-data-structures-part2.html
index 9e2da3920..5505edbd5 100644
--- a/05-data-structures-part2.html
+++ b/05-data-structures-part2.html
@@ -659,7 +659,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to Challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -942,7 +942,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to Challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>To check the last few lines it’s relatively simple as R already has a
 function for this:</p>
@@ -1001,7 +1001,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to Challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The <code>source</code> function can be used to use a script within a
 script. Assume you would like to load the same type of file over and
@@ -1052,7 +1052,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>The object <code>gapminder</code> is a data frame with columns</p>
 <ul><li>
@@ -1147,7 +1147,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/05-data-structures-part2.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-22",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/06-data-subsetting.html b/06-data-subsetting.html
index 04e5f194f..c32d736f9 100644
--- a/06-data-subsetting.html
+++ b/06-data-subsetting.html
@@ -694,7 +694,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -881,7 +881,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1134,7 +1134,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ul><li>The <strong>wrong</strong> way to do this problem is
 <code>countries==seAsia</code>. This gives a warning
@@ -1415,7 +1415,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>D</p>
 </div>
@@ -1560,7 +1560,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution to challenge 5</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb115">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1624,7 +1624,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Solution to challenge 6</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb122">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1778,7 +1778,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Solution to challenge 7</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>Fix each of the following common data frame subsetting errors:</p>
 <ol style="list-style-type: decimal"><li>Extract observations collected for the year 1957</li>
@@ -1850,7 +1850,7 @@ <h3 class="callout-title">Challenge 8<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Solution to challenge 8</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p><code>gapminder</code> is a data.frame so needs to be subsetted
 on two dimensions. <code>gapminder[1:20, ]</code> subsets the data to
@@ -1943,7 +1943,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/06-data-subsetting.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/07-control-flow.html b/07-control-flow.html
index 2123ba2e3..0b55a2a63 100644
--- a/07-control-flow.html
+++ b/07-control-flow.html
@@ -519,7 +519,7 @@ <h3 class="callout-title">Challenge 1<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to Challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>We will first see a solution to Challenge 1 which does not use the
 <code>any()</code> function. We first obtain a logical vector describing
@@ -861,7 +861,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to Challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>We can check whether the two vectors are identical using the
 <code>all()</code> function:</p>
@@ -945,7 +945,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to Challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p><strong>Step 1</strong>: We want to make sure we can extract all the
 unique values of the continent vector</p>
@@ -1024,7 +1024,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>We modify our solution to Challenge 3 by now adding two thresholds,
 <code>lowerThreshold</code> and <code>upperThreshold</code> and
@@ -1073,7 +1073,7 @@ <h3 class="callout-title">Challenge 5 - Advanced<a class="anchor" aria-label="an
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution for Challenge 5</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <p>We will use the <code>grep()</code> command that was introduced in
 the <a href="https://swcarpentry.github.io/shell-novice/07-find.html" class="external-link">Unix
@@ -1203,7 +1203,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/07-control-flow.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/08-plot-ggplot2.html b/08-plot-ggplot2.html
index 5a6a7ee39..79e32e5f3 100644
--- a/08-plot-ggplot2.html
+++ b/08-plot-ggplot2.html
@@ -1061,7 +1061,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/08-plot-ggplot2.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/09-vectorization.html b/09-vectorization.html
index 9d356cb62..d2c7a232c 100644
--- a/09-vectorization.html
+++ b/09-vectorization.html
@@ -980,7 +980,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/09-vectorization.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/10-functions.html b/10-functions.html
index 69d62a60c..bf7286531 100644
--- a/10-functions.html
+++ b/10-functions.html
@@ -523,7 +523,7 @@ <h3 class="callout-title">Challenge 1<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>Write a function called <code>kelvin_to_celsius</code> that takes a
 temperature in Kelvin and returns that temperature in Celsius</p>
@@ -579,7 +579,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>Define the function to convert directly from Fahrenheit to Celsius,
 by reusing these two functions above</p>
@@ -711,7 +711,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>Extend our previous definition of the function by adding in an
 explicit call to <code>stopifnot()</code>. Since
@@ -967,7 +967,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1024,7 +1024,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution to challenge 5</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>Write a function called <code>fence()</code> that takes two vectors
 as arguments, called <code>text</code> and <code>wrapper</code>, and
@@ -1179,7 +1179,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/10-functions.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/11-writing-data.html b/11-writing-data.html
index a02f6957b..7473a708f 100644
--- a/11-writing-data.html
+++ b/11-writing-data.html
@@ -651,7 +651,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/11-writing-data.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/12-plyr.html b/12-plyr.html
index 5b2d67657..439a24c89 100644
--- a/12-plyr.html
+++ b/12-plyr.html
@@ -973,7 +973,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/12-plyr.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/13-dplyr.html b/13-dplyr.html
index 5c23a28ce..3968b3984 100644
--- a/13-dplyr.html
+++ b/13-dplyr.html
@@ -1206,7 +1206,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/13-dplyr.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-22",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/14-tidyr.html b/14-tidyr.html
index dbb954fdb..4d2d93ffe 100644
--- a/14-tidyr.html
+++ b/14-tidyr.html
@@ -1126,7 +1126,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/14-tidyr.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-22",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/15-knitr-markdown.html b/15-knitr-markdown.html
index eddd24919..34d9aedd7 100644
--- a/15-knitr-markdown.html
+++ b/15-knitr-markdown.html
@@ -899,7 +899,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/15-knitr-markdown.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/16-wrap-up.html b/16-wrap-up.html
index 9889ece74..e96d2109c 100644
--- a/16-wrap-up.html
+++ b/16-wrap-up.html
@@ -555,7 +555,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "identifier": "https://UCL.github.io/ClinicianCoders/16-wrap-up.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/404.html b/404.html
index e9127415e..f4650f5cc 100644
--- a/404.html
+++ b/404.html
@@ -418,8 +418,8 @@ <h1>Page not found</h1>
   "url": "https://UCL.github.io/ClinicianCoders/404.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/404.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/CODE_OF_CONDUCT.html b/CODE_OF_CONDUCT.html
index fdafb24c9..110a1a92a 100644
--- a/CODE_OF_CONDUCT.html
+++ b/CODE_OF_CONDUCT.html
@@ -418,7 +418,7 @@ <h1>Contributor Code of Conduct</h1>
   "identifier": "https://UCL.github.io/ClinicianCoders/CODE_OF_CONDUCT.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/LICENSE.html b/LICENSE.html
index 74497c2c7..dcd5fb49e 100644
--- a/LICENSE.html
+++ b/LICENSE.html
@@ -469,7 +469,7 @@ <h1>Licenses</h1>
   "identifier": "https://UCL.github.io/ClinicianCoders/LICENSE.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/aio.html b/aio.html
index 97bae72a1..297b6d076 100644
--- a/aio.html
+++ b/aio.html
@@ -1728,7 +1728,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>By running these commands in the shell:</p>
 <div class="codewrapper sourceCode" id="cb1">
@@ -2766,7 +2766,7 @@ <h3 class="callout-title">Discussion 1<a class="anchor" aria-label="anchor" href
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Discussion 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>By keeping everything in a column the same, we allow ourselves to
 make simple assumptions about our data; if you can interpret one entry
@@ -2996,7 +2996,7 @@ <h4 id="print-the-data">1. Print the data<a class="anchor" aria-label="anchor" h
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Tip 1.1</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>Show the content of any variable by typing its name.</p>
 <div class="section level3">
@@ -3029,7 +3029,7 @@ <h3 class="callout-title">2. Overview of the data types<a class="anchor" aria-la
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Tip 1.2</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>In the chapter “Data types” we saw two functions that can show data
 types. One printed just a single word, the data type name. The other
@@ -3071,7 +3071,7 @@ <h4 id="which-data-type-do-we-need">3. Which data type do we need?<a class="anch
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Tip 1.3</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>Scroll up to the section about the <a href="#the-type-hierarchy">type
 hierarchy</a> to review the available data types</p>
@@ -3084,7 +3084,7 @@ <h4 class="accordion-header" id="headingSolution4">Tip 1.3</h4>
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution to Challenge 1.3</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <ul>
 <li>Weight is expressed on a continuous scale (real numbers). The R data
@@ -3118,7 +3118,7 @@ <h3 class="callout-title">4. Correct the problematic value<a class="anchor" aria
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Tip 1.4</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>Revisit the hierarchy of data types when two different data types are
 combined.</p>
@@ -3157,7 +3157,7 @@ <h4 id="convert-the-column-weight-to-the-correct-data-type">5. Convert the colum
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Tip 1.5</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The functions to convert data types start with <code>as.</code>. You
 can look for the function further up in the manuscript or use the
@@ -3348,7 +3348,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Solution to Challenge 2</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb92">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3578,7 +3578,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution9" aria-expanded="false" aria-controls="collapseSolution9">
   <h4 class="accordion-header" id="headingSolution9">Solution to Challenge 3</h4>
 </button>
-<div id="collapseSolution9" class="accordion-collapse collapse" data-bs-parent="#accordionSolution9" aria-labelledby="headingSolution9">
+<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
 <div class="accordion-body">
 <p>You get the names of an object by wrapping the object name inside
 <code>names(...)</code>. Similarly, you get the data type of the names
@@ -3623,7 +3623,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution10" aria-expanded="false" aria-controls="collapseSolution10">
   <h4 class="accordion-header" id="headingSolution10">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
 <div class="accordion-body">
 <pre><code><span><span class="va">letter_no</span> <span class="op">&lt;-</span> <span class="fl">1</span><span class="op">:</span><span class="fl">26</span>   <span class="co"># or seq(1,26)</span></span>
 <span><span class="fu">names</span><span class="op">(</span><span class="va">letter_no</span><span class="op">)</span> <span class="op">&lt;-</span> <span class="va">LETTERS</span></span>
@@ -3814,7 +3814,7 @@ <h3 class="callout-title">Challenge 5<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution11" aria-expanded="false" aria-controls="collapseSolution11">
   <h4 class="accordion-header" id="headingSolution11">Solution to Challenge 5</h4>
 </button>
-<div id="collapseSolution11" class="accordion-collapse collapse" data-bs-parent="#accordionSolution11" aria-labelledby="headingSolution11">
+<div id="collapseSolution11" class="accordion-collapse collapse" aria-labelledby="headingSolution11" data-bs-parent="#accordionSolution11">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb138">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4075,7 +4075,7 @@ <h3 class="callout-title">Challenge 6<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution12" aria-expanded="false" aria-controls="collapseSolution12">
   <h4 class="accordion-header" id="headingSolution12">Solution to Challenge 6</h4>
 </button>
-<div id="collapseSolution12" class="accordion-collapse collapse" data-bs-parent="#accordionSolution12" aria-labelledby="headingSolution12">
+<div id="collapseSolution12" class="accordion-collapse collapse" aria-labelledby="headingSolution12" data-bs-parent="#accordionSolution12">
 <div class="accordion-body">
 <p>What do you think will be the result of
 <code>length(matrix_example)</code>?</p>
@@ -4119,7 +4119,7 @@ <h3 class="callout-title">Challenge 7<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution13" aria-expanded="false" aria-controls="collapseSolution13">
   <h4 class="accordion-header" id="headingSolution13">Solution to Challenge 7</h4>
 </button>
-<div id="collapseSolution13" class="accordion-collapse collapse" data-bs-parent="#accordionSolution13" aria-labelledby="headingSolution13">
+<div id="collapseSolution13" class="accordion-collapse collapse" aria-labelledby="headingSolution13" data-bs-parent="#accordionSolution13">
 <div class="accordion-body">
 <p>Make another matrix, this time containing the numbers 1:50, with 5
 columns and 10 rows. Did the <code>matrix</code> function fill your
@@ -4161,7 +4161,7 @@ <h3 class="callout-title">Challenge 8<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution14" aria-expanded="false" aria-controls="collapseSolution14">
   <h4 class="accordion-header" id="headingSolution14">Solution to Challenge 8</h4>
 </button>
-<div id="collapseSolution14" class="accordion-collapse collapse" data-bs-parent="#accordionSolution14" aria-labelledby="headingSolution14">
+<div id="collapseSolution14" class="accordion-collapse collapse" aria-labelledby="headingSolution14" data-bs-parent="#accordionSolution14">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb173">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4213,7 +4213,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution15" aria-expanded="false" aria-controls="collapseSolution15">
   <h4 class="accordion-header" id="headingSolution15">Solution to Challenge 9</h4>
 </button>
-<div id="collapseSolution15" class="accordion-collapse collapse" data-bs-parent="#accordionSolution15" aria-labelledby="headingSolution15">
+<div id="collapseSolution15" class="accordion-collapse collapse" aria-labelledby="headingSolution15" data-bs-parent="#accordionSolution15">
 <div class="accordion-body">
 <p>Consider the R output of the matrix below:</p>
 <div class="codewrapper">
@@ -4568,7 +4568,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to Challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4858,7 +4858,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to Challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>To check the last few lines it’s relatively simple as R already has a
 function for this:</p>
@@ -4918,7 +4918,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to Challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The <code>source</code> function can be used to use a script within a
 script. Assume you would like to load the same type of file over and
@@ -4969,7 +4969,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>The object <code>gapminder</code> is a data frame with columns</p>
 <ul>
@@ -5347,7 +5347,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5540,7 +5540,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5795,7 +5795,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ul>
 <li>The <strong>wrong</strong> way to do this problem is
@@ -6086,7 +6086,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>D</p>
 </div>
@@ -6232,7 +6232,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution to challenge 5</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb115">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6296,7 +6296,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Solution to challenge 6</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb122">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6461,7 +6461,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Solution to challenge 7</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>Fix each of the following common data frame subsetting errors:</p>
 <ol style="list-style-type: decimal">
@@ -6545,7 +6545,7 @@ <h3 class="callout-title">Challenge 8<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Solution to challenge 8</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p><code>gapminder</code> is a data.frame so needs to be subsetted
@@ -6753,7 +6753,7 @@ <h3 class="callout-title">Challenge 1<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to Challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>We will first see a solution to Challenge 1 which does not use the
 <code>any()</code> function. We first obtain a logical vector describing
@@ -7096,7 +7096,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to Challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>We can check whether the two vectors are identical using the
 <code>all()</code> function:</p>
@@ -7180,7 +7180,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to Challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p><strong>Step 1</strong>: We want to make sure we can extract all the
 unique values of the continent vector</p>
@@ -7261,7 +7261,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>We modify our solution to Challenge 3 by now adding two thresholds,
 <code>lowerThreshold</code> and <code>upperThreshold</code> and
@@ -7310,7 +7310,7 @@ <h3 class="callout-title">Challenge 5 - Advanced<a class="anchor" aria-label="an
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution for Challenge 5</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <p>We will use the <code>grep()</code> command that was introduced in
 the <a href="https://swcarpentry.github.io/shell-novice/07-find.html" class="external-link">Unix
@@ -8809,7 +8809,7 @@ <h3 class="callout-title">Challenge 1<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>Write a function called <code>kelvin_to_celsius</code> that takes a
 temperature in Kelvin and returns that temperature in Celsius</p>
@@ -8866,7 +8866,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>Define the function to convert directly from Fahrenheit to Celsius,
 by reusing these two functions above</p>
@@ -9000,7 +9000,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>Extend our previous definition of the function by adding in an
 explicit call to <code>stopifnot()</code>. Since
@@ -9259,7 +9259,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -9316,7 +9316,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution to challenge 5</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>Write a function called <code>fence()</code> that takes two vectors
 as arguments, called <code>text</code> and <code>wrapper</code>, and
@@ -12474,8 +12474,8 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/aio.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/aio.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/discuss.html b/discuss.html
index d95c74160..a03ee6700 100644
--- a/discuss.html
+++ b/discuss.html
@@ -412,7 +412,7 @@ <h1>Discussion</h1>
   "identifier": "https://UCL.github.io/ClinicianCoders/discuss.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/images.html b/images.html
index a5cf6105f..9350ccaa1 100644
--- a/images.html
+++ b/images.html
@@ -613,8 +613,8 @@ <h3 id="15-knitr-markdown-figure-3">Figure 3</h3>
   "url": "https://UCL.github.io/ClinicianCoders/images.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/images.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/index.html b/index.html
index 916e75959..5b4dffc26 100644
--- a/index.html
+++ b/index.html
@@ -431,8 +431,8 @@ <h3 class="callout-title">Prerequisites<a class="anchor" aria-label="anchor" hre
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   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
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diff --git a/instructor-notes.html b/instructor-notes.html
index faca3c534..34e7873e8 100644
--- a/instructor-notes.html
+++ b/instructor-notes.html
@@ -613,8 +613,8 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
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-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
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diff --git a/instructor/01-rstudio-intro.html b/instructor/01-rstudio-intro.html
index 8a882dc21..ca78006c2 100644
--- a/instructor/01-rstudio-intro.html
+++ b/instructor/01-rstudio-intro.html
@@ -1438,7 +1438,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
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diff --git a/instructor/02-project-intro.html b/instructor/02-project-intro.html
index 775339a03..55d2e9593 100644
--- a/instructor/02-project-intro.html
+++ b/instructor/02-project-intro.html
@@ -591,7 +591,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
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 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>By running these commands in the shell:</p>
 <div class="codewrapper sourceCode" id="cb1">
@@ -789,7 +789,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
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diff --git a/instructor/03-seeking-help.html b/instructor/03-seeking-help.html
index ff7898076..141cee81d 100644
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@@ -824,7 +824,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
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diff --git a/instructor/04-data-structures-part1.html b/instructor/04-data-structures-part1.html
index 637671314..4f8e5ae76 100644
--- a/instructor/04-data-structures-part1.html
+++ b/instructor/04-data-structures-part1.html
@@ -818,7 +818,7 @@ <h3 class="callout-title">Discussion 1<a class="anchor" aria-label="anchor" href
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
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-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>By keeping everything in a column the same, we allow ourselves to
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@@ -1043,7 +1043,7 @@ <h4 id="print-the-data">1. Print the data<a class="anchor" aria-label="anchor" h
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 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>Show the content of any variable by typing its name.</p>
 <div class="section level3">
@@ -1075,7 +1075,7 @@ <h3 class="callout-title">2. Overview of the data types<a class="anchor" aria-la
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-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
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 <p>In the chapter “Data types” we saw two functions that can show data
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 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
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 <p>Scroll up to the section about the <a href="#the-type-hierarchy">type
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@@ -1127,7 +1127,7 @@ <h4 class="accordion-header" id="headingSolution4">Tip 1.3</h4>
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-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
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 <ul><li>Weight is expressed on a continuous scale (real numbers). The R data
 type for this is “double” (also known as “numeric”).</li>
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-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
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 <p>Revisit the hierarchy of data types when two different data types are
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-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
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 <p>The functions to convert data types start with <code>as.</code>. You
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 <p>You get the names of an object by wrapping the object name inside
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-<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
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 <pre><code><span><span class="va">letter_no</span> <span class="op">&lt;-</span> <span class="fl">1</span><span class="op">:</span><span class="fl">26</span>   <span class="co"># or seq(1,26)</span></span>
 <span><span class="fu">names</span><span class="op">(</span><span class="va">letter_no</span><span class="op">)</span> <span class="op">&lt;-</span> <span class="va">LETTERS</span></span>
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 <div class="codewrapper sourceCode" id="cb138">
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 <div class="accordion-body">
 <p>What do you think will be the result of
 <code>length(matrix_example)</code>?</p>
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 <p>Make another matrix, this time containing the numbers 1:50, with 5
 columns and 10 rows. Did the <code>matrix</code> function fill your
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 <div class="codewrapper sourceCode" id="cb173">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
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 </button>
-<div id="collapseSolution15" class="accordion-collapse collapse" data-bs-parent="#accordionSolution15" aria-labelledby="headingSolution15">
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 <div class="accordion-body">
 <p>Consider the R output of the matrix below:</p>
 <div class="codewrapper">
@@ -2336,7 +2336,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
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diff --git a/instructor/05-data-structures-part2.html b/instructor/05-data-structures-part2.html
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 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
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 <div class="accordion-body">
 <p>To check the last few lines it’s relatively simple as R already has a
 function for this:</p>
@@ -1003,7 +1003,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
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 <div class="accordion-body">
 <p>The <code>source</code> function can be used to use a script within a
 script. Assume you would like to load the same type of file over and
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 <p>The object <code>gapminder</code> is a data frame with columns</p>
 <ul><li>
@@ -1149,7 +1149,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
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diff --git a/instructor/06-data-subsetting.html b/instructor/06-data-subsetting.html
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 <div class="codewrapper sourceCode" id="cb34">
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 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
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 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1136,7 +1136,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
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 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
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 <div class="accordion-body">
 <ul><li>The <strong>wrong</strong> way to do this problem is
 <code>countries==seAsia</code>. This gives a warning
@@ -1417,7 +1417,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
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-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
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 <div class="accordion-body">
 <p>D</p>
 </div>
@@ -1562,7 +1562,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
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 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb115">
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 <p>Fix each of the following common data frame subsetting errors:</p>
 <ol style="list-style-type: decimal"><li>Extract observations collected for the year 1957</li>
@@ -1852,7 +1852,7 @@ <h3 class="callout-title">Challenge 8<a class="anchor" aria-label="anchor" href=
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 <ol style="list-style-type: decimal"><li><p><code>gapminder</code> is a data.frame so needs to be subsetted
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@@ -1945,7 +1945,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
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 <p>We will first see a solution to Challenge 1 which does not use the
 <code>any()</code> function. We first obtain a logical vector describing
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 <p>We can check whether the two vectors are identical using the
 <code>all()</code> function:</p>
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 <p><strong>Step 1</strong>: We want to make sure we can extract all the
 unique values of the continent vector</p>
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 <p>We modify our solution to Challenge 3 by now adding two thresholds,
 <code>lowerThreshold</code> and <code>upperThreshold</code> and
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 <p>We will use the <code>grep()</code> command that was introduced in
 the <a href="https://swcarpentry.github.io/shell-novice/07-find.html" class="external-link">Unix
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 <p>Write a function called <code>kelvin_to_celsius</code> that takes a
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 <p>Define the function to convert directly from Fahrenheit to Celsius,
 by reusing these two functions above</p>
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 <p>Extend our previous definition of the function by adding in an
 explicit call to <code>stopifnot()</code>. Since
@@ -969,7 +969,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
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 <p>Write a function called <code>fence()</code> that takes two vectors
 as arguments, called <code>text</code> and <code>wrapper</code>, and
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diff --git a/instructor/14-tidyr.html b/instructor/14-tidyr.html
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index b76ec1eae..7a92ed9b9 100644
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diff --git a/instructor/aio.html b/instructor/aio.html
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 <p>By running these commands in the shell:</p>
 <div class="codewrapper sourceCode" id="cb1">
@@ -2772,7 +2772,7 @@ <h3 class="callout-title">Discussion 1<a class="anchor" aria-label="anchor" href
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-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
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 <p>By keeping everything in a column the same, we allow ourselves to
 make simple assumptions about our data; if you can interpret one entry
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 <p>Show the content of any variable by typing its name.</p>
 <div class="section level3">
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 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
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 <p>In the chapter “Data types” we saw two functions that can show data
 types. One printed just a single word, the data type name. The other
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 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
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 <div class="accordion-body">
 <p>Scroll up to the section about the <a href="#the-type-hierarchy">type
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@@ -3090,7 +3090,7 @@ <h4 class="accordion-header" id="headingSolution4">Tip 1.3</h4>
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-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
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 <ul>
 <li>Weight is expressed on a continuous scale (real numbers). The R data
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 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <p>Revisit the hierarchy of data types when two different data types are
 combined.</p>
@@ -3163,7 +3163,7 @@ <h4 id="convert-the-column-weight-to-the-correct-data-type">5. Convert the colum
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Tip 1.5</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>The functions to convert data types start with <code>as.</code>. You
 can look for the function further up in the manuscript or use the
@@ -3354,7 +3354,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Solution to Challenge 2</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb92">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3584,7 +3584,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution9" aria-expanded="false" aria-controls="collapseSolution9">
   <h4 class="accordion-header" id="headingSolution9">Solution to Challenge 3</h4>
 </button>
-<div id="collapseSolution9" class="accordion-collapse collapse" data-bs-parent="#accordionSolution9" aria-labelledby="headingSolution9">
+<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
 <div class="accordion-body">
 <p>You get the names of an object by wrapping the object name inside
 <code>names(...)</code>. Similarly, you get the data type of the names
@@ -3629,7 +3629,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution10" aria-expanded="false" aria-controls="collapseSolution10">
   <h4 class="accordion-header" id="headingSolution10">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
 <div class="accordion-body">
 <pre><code><span><span class="va">letter_no</span> <span class="op">&lt;-</span> <span class="fl">1</span><span class="op">:</span><span class="fl">26</span>   <span class="co"># or seq(1,26)</span></span>
 <span><span class="fu">names</span><span class="op">(</span><span class="va">letter_no</span><span class="op">)</span> <span class="op">&lt;-</span> <span class="va">LETTERS</span></span>
@@ -3820,7 +3820,7 @@ <h3 class="callout-title">Challenge 5<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution11" aria-expanded="false" aria-controls="collapseSolution11">
   <h4 class="accordion-header" id="headingSolution11">Solution to Challenge 5</h4>
 </button>
-<div id="collapseSolution11" class="accordion-collapse collapse" data-bs-parent="#accordionSolution11" aria-labelledby="headingSolution11">
+<div id="collapseSolution11" class="accordion-collapse collapse" aria-labelledby="headingSolution11" data-bs-parent="#accordionSolution11">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb138">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4081,7 +4081,7 @@ <h3 class="callout-title">Challenge 6<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution12" aria-expanded="false" aria-controls="collapseSolution12">
   <h4 class="accordion-header" id="headingSolution12">Solution to Challenge 6</h4>
 </button>
-<div id="collapseSolution12" class="accordion-collapse collapse" data-bs-parent="#accordionSolution12" aria-labelledby="headingSolution12">
+<div id="collapseSolution12" class="accordion-collapse collapse" aria-labelledby="headingSolution12" data-bs-parent="#accordionSolution12">
 <div class="accordion-body">
 <p>What do you think will be the result of
 <code>length(matrix_example)</code>?</p>
@@ -4125,7 +4125,7 @@ <h3 class="callout-title">Challenge 7<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution13" aria-expanded="false" aria-controls="collapseSolution13">
   <h4 class="accordion-header" id="headingSolution13">Solution to Challenge 7</h4>
 </button>
-<div id="collapseSolution13" class="accordion-collapse collapse" data-bs-parent="#accordionSolution13" aria-labelledby="headingSolution13">
+<div id="collapseSolution13" class="accordion-collapse collapse" aria-labelledby="headingSolution13" data-bs-parent="#accordionSolution13">
 <div class="accordion-body">
 <p>Make another matrix, this time containing the numbers 1:50, with 5
 columns and 10 rows. Did the <code>matrix</code> function fill your
@@ -4167,7 +4167,7 @@ <h3 class="callout-title">Challenge 8<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution14" aria-expanded="false" aria-controls="collapseSolution14">
   <h4 class="accordion-header" id="headingSolution14">Solution to Challenge 8</h4>
 </button>
-<div id="collapseSolution14" class="accordion-collapse collapse" data-bs-parent="#accordionSolution14" aria-labelledby="headingSolution14">
+<div id="collapseSolution14" class="accordion-collapse collapse" aria-labelledby="headingSolution14" data-bs-parent="#accordionSolution14">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb173">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4219,7 +4219,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution15" aria-expanded="false" aria-controls="collapseSolution15">
   <h4 class="accordion-header" id="headingSolution15">Solution to Challenge 9</h4>
 </button>
-<div id="collapseSolution15" class="accordion-collapse collapse" data-bs-parent="#accordionSolution15" aria-labelledby="headingSolution15">
+<div id="collapseSolution15" class="accordion-collapse collapse" aria-labelledby="headingSolution15" data-bs-parent="#accordionSolution15">
 <div class="accordion-body">
 <p>Consider the R output of the matrix below:</p>
 <div class="codewrapper">
@@ -4575,7 +4575,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to Challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb28">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4865,7 +4865,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to Challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>To check the last few lines it’s relatively simple as R already has a
 function for this:</p>
@@ -4925,7 +4925,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to Challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The <code>source</code> function can be used to use a script within a
 script. Assume you would like to load the same type of file over and
@@ -4976,7 +4976,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>The object <code>gapminder</code> is a data frame with columns</p>
 <ul>
@@ -5355,7 +5355,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5548,7 +5548,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5803,7 +5803,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ul>
 <li>The <strong>wrong</strong> way to do this problem is
@@ -6094,7 +6094,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>D</p>
 </div>
@@ -6240,7 +6240,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution to challenge 5</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb115">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6304,7 +6304,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution6" aria-expanded="false" aria-controls="collapseSolution6">
   <h4 class="accordion-header" id="headingSolution6">Solution to challenge 6</h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb122">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6469,7 +6469,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution7" aria-expanded="false" aria-controls="collapseSolution7">
   <h4 class="accordion-header" id="headingSolution7">Solution to challenge 7</h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>Fix each of the following common data frame subsetting errors:</p>
 <ol style="list-style-type: decimal">
@@ -6553,7 +6553,7 @@ <h3 class="callout-title">Challenge 8<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution8" aria-expanded="false" aria-controls="collapseSolution8">
   <h4 class="accordion-header" id="headingSolution8">Solution to challenge 8</h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p><code>gapminder</code> is a data.frame so needs to be subsetted
@@ -6762,7 +6762,7 @@ <h3 class="callout-title">Challenge 1<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to Challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>We will first see a solution to Challenge 1 which does not use the
 <code>any()</code> function. We first obtain a logical vector describing
@@ -7105,7 +7105,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to Challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>We can check whether the two vectors are identical using the
 <code>all()</code> function:</p>
@@ -7189,7 +7189,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to Challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p><strong>Step 1</strong>: We want to make sure we can extract all the
 unique values of the continent vector</p>
@@ -7270,7 +7270,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to Challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>We modify our solution to Challenge 3 by now adding two thresholds,
 <code>lowerThreshold</code> and <code>upperThreshold</code> and
@@ -7319,7 +7319,7 @@ <h3 class="callout-title">Challenge 5 - Advanced<a class="anchor" aria-label="an
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution for Challenge 5</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <p>We will use the <code>grep()</code> command that was introduced in
 the <a href="https://swcarpentry.github.io/shell-novice/07-find.html" class="external-link">Unix
@@ -8821,7 +8821,7 @@ <h3 class="callout-title">Challenge 1<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution1" aria-expanded="false" aria-controls="collapseSolution1">
   <h4 class="accordion-header" id="headingSolution1">Solution to challenge 1</h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>Write a function called <code>kelvin_to_celsius</code> that takes a
 temperature in Kelvin and returns that temperature in Celsius</p>
@@ -8878,7 +8878,7 @@ <h3 class="callout-title">Challenge 2<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution2" aria-expanded="false" aria-controls="collapseSolution2">
   <h4 class="accordion-header" id="headingSolution2">Solution to challenge 2</h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>Define the function to convert directly from Fahrenheit to Celsius,
 by reusing these two functions above</p>
@@ -9012,7 +9012,7 @@ <h3 class="callout-title">Challenge 3<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution3" aria-expanded="false" aria-controls="collapseSolution3">
   <h4 class="accordion-header" id="headingSolution3">Solution to challenge 3</h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>Extend our previous definition of the function by adding in an
 explicit call to <code>stopifnot()</code>. Since
@@ -9271,7 +9271,7 @@ <h3 class="callout-title">Challenge 4<a class="anchor" aria-label="anchor" href=
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution4" aria-expanded="false" aria-controls="collapseSolution4">
   <h4 class="accordion-header" id="headingSolution4">Solution to challenge 4</h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb32">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -9328,7 +9328,7 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <button class="accordion-button solution-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSolution5" aria-expanded="false" aria-controls="collapseSolution5">
   <h4 class="accordion-header" id="headingSolution5">Solution to challenge 5</h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>Write a function called <code>fence()</code> that takes two vectors
 as arguments, called <code>text</code> and <code>wrapper</code>, and
@@ -12492,8 +12492,8 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/aio.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/aio.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/instructor/discuss.html b/instructor/discuss.html
index 49368abe6..7813a4b5c 100644
--- a/instructor/discuss.html
+++ b/instructor/discuss.html
@@ -414,7 +414,7 @@ <h1>Discussion</h1>
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/discuss.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/instructor/images.html b/instructor/images.html
index a59093726..a51e9ff52 100644
--- a/instructor/images.html
+++ b/instructor/images.html
@@ -615,8 +615,8 @@ <h3 id="15-knitr-markdown-figure-3">Figure 3</h3>
   "url": "https://UCL.github.io/ClinicianCoders/instructor/images.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/images.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/instructor/index.html b/instructor/index.html
index 82e782788..3ceb635c5 100644
--- a/instructor/index.html
+++ b/instructor/index.html
@@ -592,8 +592,8 @@ <h3 class="callout-title">Prerequisites<a class="anchor" aria-label="anchor" hre
   "url": "https://UCL.github.io/ClinicianCoders/instructor/index.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/index.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/instructor/instructor-notes.html b/instructor/instructor-notes.html
index 8d56d7ce1..0fb2e00fb 100644
--- a/instructor/instructor-notes.html
+++ b/instructor/instructor-notes.html
@@ -631,8 +631,8 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
   "url": "https://UCL.github.io/ClinicianCoders/instructor/instructor-notes.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/instructor-notes.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/instructor/key-points.html b/instructor/key-points.html
index b69d01480..3a36f07df 100644
--- a/instructor/key-points.html
+++ b/instructor/key-points.html
@@ -590,8 +590,8 @@ <h2 class="accordion-header" id="flush-headingTwelve">
   "url": "https://UCL.github.io/ClinicianCoders/instructor/key-points.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/key-points.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/instructor/profiles.html b/instructor/profiles.html
index 983a0ad69..a1779b123 100644
--- a/instructor/profiles.html
+++ b/instructor/profiles.html
@@ -369,8 +369,8 @@ <h1>Learner Profiles</h1>
   "url": "https://UCL.github.io/ClinicianCoders/instructor/profiles.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/profiles.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/instructor/reference.html b/instructor/reference.html
index 783bd135a..a5822387f 100644
--- a/instructor/reference.html
+++ b/instructor/reference.html
@@ -932,7 +932,7 @@ <h1>Reference</h1>
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/reference.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/key-points.html b/key-points.html
index 7ec07a1b3..d9cf4ebf1 100644
--- a/key-points.html
+++ b/key-points.html
@@ -588,8 +588,8 @@ <h2 class="accordion-header" id="flush-headingTwelve">
   "url": "https://UCL.github.io/ClinicianCoders/key-points.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/key-points.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/pkgdown.yml b/pkgdown.yml
index ad576c8ee..590df5cd0 100644
--- a/pkgdown.yml
+++ b/pkgdown.yml
@@ -2,5 +2,5 @@ pandoc: 2.19.2
 pkgdown: 2.0.7
 pkgdown_sha: ~
 articles: {}
-last_built: 2024-02-04T17:35Z
+last_built: 2024-02-06T00:22Z
 
diff --git a/profiles.html b/profiles.html
index 0855c60d5..755b16ac9 100644
--- a/profiles.html
+++ b/profiles.html
@@ -369,8 +369,8 @@ <h1>Learner Profiles</h1>
   "url": "https://UCL.github.io/ClinicianCoders/profiles.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/profiles.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-02-04",
-  "datePublished": "2024-02-04"
+  "dateModified": "2024-02-06",
+  "datePublished": "2024-02-06"
 }
 
   </script><script>
diff --git a/reference.html b/reference.html
index 2917890a6..becfa0be0 100644
--- a/reference.html
+++ b/reference.html
@@ -930,7 +930,7 @@ <h1>Reference</h1>
   "identifier": "https://UCL.github.io/ClinicianCoders/reference.html",
   "dateCreated": "2023-10-26",
   "dateModified": "2024-01-04",
-  "datePublished": "2024-02-04"
+  "datePublished": "2024-02-06"
 }
 
   </script><script>