diff --git a/Sprint-2/1-key-errors/0.js b/Sprint-2/1-key-errors/0.js
index 653d6f5a07..2bd6280251 100644
--- a/Sprint-2/1-key-errors/0.js
+++ b/Sprint-2/1-key-errors/0.js
@@ -1,13 +1,36 @@
 // Predict and explain first...
+
 //  =============> write your prediction here
+// str is already a declared variable fed into the capitalise function, the function attempts
+// to declare the variable again, this may throw an error.
+
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
+
+// Error:
+
+// let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+// SyntaxError: Identifier 'str' has already been declared
+
+
+/* Original Code:
+
 function capitalise(str) {
   let str = `${str[0].toUpperCase()}${str.slice(1)}`;
   return str;
-}
+} 
+
+*/
 
 // =============> write your explanation here
+// As predicted, an already declared variable cannot be declared again
+
 // =============> write your new code here
+
+function capitalise(str) {
+  str = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return str;
+}
+
diff --git a/Sprint-2/1-key-errors/1.js b/Sprint-2/1-key-errors/1.js
index f2d56151f4..4f58dbf3fb 100644
--- a/Sprint-2/1-key-errors/1.js
+++ b/Sprint-2/1-key-errors/1.js
@@ -1,10 +1,14 @@
 // Predict and explain first...
-
 // Why will an error occur when this program runs?
+
 // =============> write your prediction here
+// Assuming we define decimalNumber for the function (otherwise that will throw an error)
+// then we run into the same problem as the last exercise, const decimalNumber = 0.5;
+// is trying to define a variable that has already been determined
 
 // Try playing computer with the example to work out what is going on
 
+/* Original code:
 function convertToPercentage(decimalNumber) {
   const decimalNumber = 0.5;
   const percentage = `${decimalNumber * 100}%`;
@@ -13,8 +17,20 @@ function convertToPercentage(decimalNumber) {
 }
 
 console.log(decimalNumber);
+*/
 
 // =============> write your explanation here
+// Uncaught SyntaxError: Identifier 'decimalNumber' has already been declared
+// As predicted the function is trying to declare a variable that has already been determined
 
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+
+function convertToPercentage(decimalNumber) {
+  decimalNumber = 0.5;
+  const percentage = `${decimalNumber * 100}%`;
+
+  return percentage;
+}
+
+console.log(decimalNumber);
\ 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..c57119a27b 100644
--- a/Sprint-2/1-key-errors/2.js
+++ b/Sprint-2/1-key-errors/2.js
@@ -4,17 +4,27 @@
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+// num hasn't been defined, that will throw an error
 
+/*
 function square(3) {
-    return num * num;
+    return num3 * num3;
 }
+*/
 
 // =============> write the error message here
+// Uncaught SyntaxError: Unexpected number
 
 // =============> explain this error message here
+// the error appears in the line before, a function has to take defined parameters, these
+// parameters cannot be represented by numbers (or at least begin with numbers)
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
 
+function square(num) {
+    return num * num;
+}
+
 
diff --git a/Sprint-2/2-mandatory-debug/0.js b/Sprint-2/2-mandatory-debug/0.js
index b27511b417..f8110b413d 100644
--- a/Sprint-2/2-mandatory-debug/0.js
+++ b/Sprint-2/2-mandatory-debug/0.js
@@ -1,14 +1,27 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+// The multiple function doesn't return anything
+// the console log that calls the multiple function will not receive anything back, this 
+// may cause an error
 
+/* Original code:
 function multiply(a, b) {
   console.log(a * b);
 }
 
 console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
+*/
 
 // =============> write your explanation here
+// code works, however the log gave 'undefined' instead of the multiplication output
+// this is because the multiply function doesn't return any value
 
 // 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..8c2ca8bcaa 100644
--- a/Sprint-2/2-mandatory-debug/1.js
+++ b/Sprint-2/2-mandatory-debug/1.js
@@ -1,13 +1,24 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// the sum function won't return anything to the console.log
+// because the semicolon ends that line of logic
 
+/* Original code:
 function sum(a, b) {
   return;
   a + b;
 }
 
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
+*/
 
 // =============> write your explanation here
+// As before, the function returns "undefined" as nothing is returned
+
 // 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..c6e6456097 100644
--- a/Sprint-2/2-mandatory-debug/2.js
+++ b/Sprint-2/2-mandatory-debug/2.js
@@ -2,7 +2,10 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+// the function does not pass through a parameter, therefore it will always
+// call the defined variable num as 103, giving 3 as an output each time
 
+/* Original code:
 const num = 103;
 
 function getLastDigit() {
@@ -12,13 +15,32 @@ function getLastDigit() {
 console.log(`The last digit of 42 is ${getLastDigit(42)}`);
 console.log(`The last digit of 105 is ${getLastDigit(105)}`);
 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
+/*
+The last digit of 42 is 3
+The last digit of 105 is 3
+The last digit of 806 is 3
+*/
+
 // Explain why the output is the way it is
 // =============> write your explanation here
+// there is no parameter for the function
+
 // Finally, correct the code to fix the problem
 // =============> write your new code here
 
+const num = 103;
+
+function getLastDigit(num) {
+  return num.toString().slice(-1);
+}
+
+console.log(`The last digit of 42 is ${getLastDigit(42)}`);
+console.log(`The last digit of 105 is ${getLastDigit(105)}`);
+console.log(`The last digit of 806 is ${getLastDigit(806)}`);
+
 // 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..e7bc3c8f2d 100644
--- a/Sprint-2/3-mandatory-implement/1-bmi.js
+++ b/Sprint-2/3-mandatory-implement/1-bmi.js
@@ -15,5 +15,5 @@
 // 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
+    return (weight / (height^2)).toFixed(1)
 }
\ 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..22226a68ed 100644
--- a/Sprint-2/3-mandatory-implement/2-cases.js
+++ b/Sprint-2/3-mandatory-implement/2-cases.js
@@ -14,3 +14,17 @@
 // 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 upperSnakeCase(str) {
+    const upperCaseStr = str.toUpperCase();
+    return upperCaseStr.replaceAll(" ","_");
+}
+
+//tests
+console.log(upperSnakeCase("hello world"));
+console.log(upperSnakeCase("hello       world"));
+console.log(upperSnakeCase("h e l l o w o r l d "));
+console.log(upperSnakeCase("   hello world    "));
+console.log(upperSnakeCase("hello 5555 world 6666 "));
+console.log(upperSnakeCase("hello world the quick brown fox jumps over the lazy dog"));
+
diff --git a/Sprint-2/3-mandatory-implement/3-to-pounds.js b/Sprint-2/3-mandatory-implement/3-to-pounds.js
index 6265a1a703..34667bf70d 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
+
+const penceString = "399p";
+
+function toPounds(penceString) {
+    const penceStringWithoutTrailingP = penceString.substring(0, penceString.length - 1);
+    const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+    const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2);
+    const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2).padEnd(2, "0");
+    return `£${pounds}.${pence}`
+}
+
+//Tests
+console.log(toPounds("399p"))
+console.log(toPounds("3599p"))
+console.log(toPounds("390p"))
+console.log(toPounds("9p"))
+console.log(toPounds("666399p"))
+console.log(toPounds("30000001p"))
+console.log(toPounds("99p"))
+console.log(toPounds("300p"))
\ 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 17127bc01e..7157dfadec 100644
--- a/Sprint-2/4-mandatory-interpret/time-format.js
+++ b/Sprint-2/4-mandatory-interpret/time-format.js
@@ -22,17 +22,26 @@ function formatTimeDisplay(seconds) {
 
 // a) When formatTimeDisplay is called how many times will pad be called?
 // =============> write your answer here
+// 3
 
 // 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
+// 0
 
 // c) What is the return value of pad is called for the first time?
 // =============> write your answer here
+// 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
+// 1
+// When pad is called for the last time it is here pad(remainingSeconds)
+// remaining seconds = seconds % 60 = 61 % 60 = 1
 
 // e) What is the return value of pad when it is called for the last time in this program?  Explain your answer
 // =============> write your answer here
+// 01
+// when pad is called it takes the num, in this case 1, and pads it out to two digits by adding zeros at the front
+// so 1 becomes 01