diff --git a/Sprint-2/1-key-errors/0.js b/Sprint-2/1-key-errors/0.js
index 653d6f5a07..1515107074 100644
--- a/Sprint-2/1-key-errors/0.js
+++ b/Sprint-2/1-key-errors/0.js
@@ -1,5 +1,7 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// The function will not work because the variable str is the input to the function.
+// Hence, this will throw an error that says that the variable str is already declared.
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
@@ -10,4 +12,12 @@ function capitalise(str) {
 }
 
 // =============> write your explanation here
+// The error message is 'Uncaught SyntaxError: Identifier 'str' has already been declared.'
+// Like what I have explained about, the variable str is the input for the function, so it cannot be declared again with let.
+// You need to make a new variable with a new name in order for the function to work.
+
 // =============> write your new code here
+function capitalise(str) {
+  let capitalisedStr = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return capitalisedStr;
+}
\ No newline at end of file
diff --git a/Sprint-2/1-key-errors/1.js b/Sprint-2/1-key-errors/1.js
index f2d56151f4..f80385184f 100644
--- a/Sprint-2/1-key-errors/1.js
+++ b/Sprint-2/1-key-errors/1.js
@@ -2,6 +2,7 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
+// It will throw an error because decimalNumber is the input for the function, but below we are trying to declare it again using const.
 
 // Try playing computer with the example to work out what is going on
 
@@ -15,6 +16,12 @@ function convertToPercentage(decimalNumber) {
 console.log(decimalNumber);
 
 // =============> write your explanation here
+// This function would not run because the variable decimalNumber is declared twice.
+// In order for it to work, another variable with a different name must be created.
 
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+function convertToPercentage (decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+  return percentage;
+}
\ No newline at end of file
diff --git a/Sprint-2/1-key-errors/2.js b/Sprint-2/1-key-errors/2.js
index aad57f7cfe..aa0a2e4918 100644
--- a/Sprint-2/1-key-errors/2.js
+++ b/Sprint-2/1-key-errors/2.js
@@ -4,17 +4,24 @@
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+// There will be an error because the name of the input variable is not defined and we are just putting a number which will throw 'unexpected number' error.
+// and likewise, the variable num is undefined.
 
-function square(3) {
-    return num * num;
-}
+//function square(3) {
+//    return num * num;
+//}
 
 // =============> write the error message here
+// Uncaught SyntaxError: Unexpected number
 
 // =============> explain this error message here
+// This error happens when numeral is improperly positioned/used
+// In this case, when declaring a function we should always first declare what is the name of the input parameter
+// (instead of immediately inserting the parameter).
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
-
-
+function square(num) {
+    return num * num;
+}
\ No newline at end of file
diff --git a/Sprint-2/2-mandatory-debug/0.js b/Sprint-2/2-mandatory-debug/0.js
index b27511b417..20bc2516d5 100644
--- a/Sprint-2/2-mandatory-debug/0.js
+++ b/Sprint-2/2-mandatory-debug/0.js
@@ -1,6 +1,9 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+// My prediction is that the second console log will not print what is intended because in the function, the last line is console.log
+// Console.log will return nothing (undefined). Instead, the last line should've been return.
+// Using return will make the second console log print the result of the function (instead of undefined).
 
 function multiply(a, b) {
   console.log(a * b);
@@ -11,4 +14,10 @@ console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
 // =============> write your explanation here
 
 // Finally, correct the code to fix the problem
+
 //  =============> write your new code here
+function multiply(a,b) {
+  return a*b;
+}
+
+console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
\ No newline at end of file
diff --git a/Sprint-2/2-mandatory-debug/1.js b/Sprint-2/2-mandatory-debug/1.js
index 37cedfbcfd..7dab236020 100644
--- a/Sprint-2/2-mandatory-debug/1.js
+++ b/Sprint-2/2-mandatory-debug/1.js
@@ -1,5 +1,7 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// Return will return nothing since no value is assigned to it.
+// The line a + b never runs because a function ends with 'return'.
 
 function sum(a, b) {
   return;
@@ -9,5 +11,11 @@ function sum(a, b) {
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
 // =============> write your explanation here
+// The console log will print 'undefined' on the call function.
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+function sum(a, b) {
+  return a + b;
+}
+
+console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
\ No newline at end of file
diff --git a/Sprint-2/2-mandatory-debug/2.js b/Sprint-2/2-mandatory-debug/2.js
index 57d3f5dc35..b7b7969bab 100644
--- a/Sprint-2/2-mandatory-debug/2.js
+++ b/Sprint-2/2-mandatory-debug/2.js
@@ -2,6 +2,8 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+// The function will not run as intended because the parameter is not set
+// Instead it always uses the variable num, so it will always only return that variable's last digit.
 
 const num = 103;
 
@@ -15,10 +17,16 @@ console.log(`The last digit of 806 is ${getLastDigit(806)}`);
 
 // Now run the code and compare the output to your prediction
 // =============> write the output here
+// All outputs are "3", which is the last digit of the variable num, 103.
 // Explain why the output is the way it is
 // =============> write your explanation here
+// It is because no parameter is set on the function and it instead always uses the variable num.
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+function getLastDigit(number) {
+  return number.toString().slice(-1);
+}
+
 
 // This program should tell the user the last digit of each number.
 // Explain why getLastDigit is not working properly - correct the problem
diff --git a/Sprint-2/3-mandatory-implement/1-bmi.js b/Sprint-2/3-mandatory-implement/1-bmi.js
index 17b1cbde1b..ddf7174dcd 100644
--- a/Sprint-2/3-mandatory-implement/1-bmi.js
+++ b/Sprint-2/3-mandatory-implement/1-bmi.js
@@ -15,5 +15,8 @@
 // It should return their Body Mass Index to 1 decimal place
 
 function calculateBMI(weight, height) {
-    // return the BMI of someone based off their weight and height
+    const squaredHeight = height ** 2;
+    const dividedWeight = weight / squaredHeight;
+    const bmi = dividedWeight.toFixed(1);
+    return bmi;
 }
\ No newline at end of file
diff --git a/Sprint-2/3-mandatory-implement/2-cases.js b/Sprint-2/3-mandatory-implement/2-cases.js
index 5b0ef77ad9..5a36fd073c 100644
--- a/Sprint-2/3-mandatory-implement/2-cases.js
+++ b/Sprint-2/3-mandatory-implement/2-cases.js
@@ -14,3 +14,7 @@
 // You will need to come up with an appropriate name for the function
 // Use the MDN string documentation to help you find a solution
 // This might help https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase
+
+function toUpperSnakeCase(string) {
+    return string.split(" ").join("_").toUpperCase();
+}
\ No newline at end of file
diff --git a/Sprint-2/3-mandatory-implement/3-to-pounds.js b/Sprint-2/3-mandatory-implement/3-to-pounds.js
index 6265a1a703..cee2415012 100644
--- a/Sprint-2/3-mandatory-implement/3-to-pounds.js
+++ b/Sprint-2/3-mandatory-implement/3-to-pounds.js
@@ -4,3 +4,23 @@
 // You will need to declare a function called toPounds with an appropriately named parameter.
 
 // You should call this function a number of times to check it works for different inputs
+
+function toPounds(penceString) {
+    // remove the "p"
+    const penceStringWithoutP = penceString.replace("p", "");
+
+    // separate pounds and pence
+    let pence = penceStringWithoutP.slice(-2).padStart(2, "0");
+    let pounds = penceStringWithoutP.slice(0, -2).padStart(1, "0");
+
+    // convert to number and format with commas
+    pounds = Number(pounds).toLocaleString('en-GB'); 
+
+    return `£${pounds}.${pence}`;
+}
+
+// examples
+console.log(toPounds("5p"));        // £0.05
+console.log(toPounds("99p"));       // £0.99
+console.log(toPounds("1234p"));     // £12.34
+console.log(toPounds("1234567p"));  // £12,345.67
\ No newline at end of file
diff --git a/Sprint-2/4-mandatory-interpret/time-format.js b/Sprint-2/4-mandatory-interpret/time-format.js
index 7c98eb0e8c..85ede0eb57 100644
--- a/Sprint-2/4-mandatory-interpret/time-format.js
+++ b/Sprint-2/4-mandatory-interpret/time-format.js
@@ -17,18 +17,33 @@ function formatTimeDisplay(seconds) {
 // Questions
 
 // a) When formatTimeDisplay is called how many times will pad be called?
-// =============> write your answer here
+// 3 times
 
 // Call formatTimeDisplay with an input of 61, now answer the following:
 
 // b) What is the value assigned to num when pad is called for the first time?
-// =============> write your answer here
+// The value assigned to num when pad is called for the first time is the variable TotalHours
+// totalHours = (totalMinutes - remainingMinutes) / 60
+// totalMinutes = (seconds - remainingSeconds) / 60
+// remainingMinutes = totalMinutes % 60
+// remainingSeconds = seconds % 60 = 61 % 60 = 1
+// totalMinutes = (61 - 1) / 60 = 1
+// remainingMinutes = 1 % 60 = 1
+// totalHours = (1 - 1) / 60 = 0
+// So, the value assigned to num when pad is called for the first time is 0.
 
 // c) What is the return value of pad is called for the first time?
-// =============> write your answer here
+// The return value of pad when it is called for the first time is "00".
+// First, 0 is turned into string --> "0".
+// Then, a pad of 0 is added at the start so the string length will be 2.
+// Hence, the return value is "00".
 
 // d) What is the value assigned to num when pad is called for the last time in this program?  Explain your answer
-// =============> write your answer here
+// The value assigned to num when pad is called for the last time is the variable remainingSeconds.
+// As calculated above, remainingSeconds = 1.
 
 // e) What is the return value assigned to num when pad is called for the last time in this program?  Explain your answer
-// =============> write your answer here
+// The return value of pad when it is called for the last time is "01".
+// First, 1 is turned into string --> "1".
+// Then, a pad of 0 is added at the start so the string length will be 2.
+// Hence, the return value is "01".
\ No newline at end of file
diff --git a/Sprint-2/5-stretch-extend/format-time.js b/Sprint-2/5-stretch-extend/format-time.js
index 32a32e66b8..61731bfec3 100644
--- a/Sprint-2/5-stretch-extend/format-time.js
+++ b/Sprint-2/5-stretch-extend/format-time.js
@@ -2,14 +2,42 @@
 // Make sure to do the prep before you do the coursework
 // Your task is to write tests for as many different groups of input data or edge cases as you can, and fix any bugs you find.
 
+//function formatAs12HourClock(time) {
+//  const hours = Number(time.slice(0, 2));
+//  if (hours > 12) {
+//    return `${hours - 12}:00 pm`;
+//  }
+//  return `${time} am`;
+//}
+
+// Observation:
+// the minutes are hardcoded for hours > 12
+// incorrect midnight (00:00) it will return 00:00 am instead of 12:00 am
+// incorrect noon (12:00) it will return 12:00 am instead of 12:00 pm
+// no padding for single digit hours
+
+// Fixing the function:
 function formatAs12HourClock(time) {
-  const hours = Number(time.slice(0, 2));
-  if (hours > 12) {
-    return `${hours - 12}:00 pm`;
+  let hours = Number(time.slice(0, 2)); // get hours as number
+  const minutes = time.slice(2);        // keep the minutes string
+  let suffix = "am";
+
+  if (hours === 0) {
+    hours = 12; // midnight
+  } else if (hours === 12) {
+    suffix = "pm"; // noon
+  } else if (hours > 12) {
+    hours -= 12;
+    suffix = "pm";
   }
-  return `${time} am`;
+
+  // pad single-digit hours with leading zero
+  const hoursStr = String(hours).padStart(2, "0");
+
+  return `${hoursStr}${minutes} ${suffix}`;
 }
 
+
 const currentOutput = formatAs12HourClock("08:00");
 const targetOutput = "08:00 am";
 console.assert(
@@ -23,3 +51,17 @@ console.assert(
   currentOutput2 === targetOutput2,
   `current output: ${currentOutput2}, target output: ${targetOutput2}`
 );
+
+const currentOutput3 = formatAs12HourClock("00:00");
+const targetOutput3 = "12:00 am";
+console.assert(
+  currentOutput3 === targetOutput3,
+  `current output: ${currentOutput3}, target output: ${targetOutput3}`
+);
+
+const currentOutput4 = formatAs12HourClock("12:00");
+const targetOutput4 = "12:00 pm";
+console.assert(
+  currentOutput4 === targetOutput4,
+  `current output: ${currentOutput4}, target output: ${targetOutput4}`
+);
\ No newline at end of file