Fix variable redeclaration issues and enhance error prediction comments in key error examples

Author: JohnRob-jnr

Sprint-2/1-key-errors/0.js

@@ -1,13 +1,12 @@
 // Predict and explain first...
-//  =============> write your prediction here
 
-// call the function capitalise with a string input
+//  =============> write your prediction here
+//A) You are likely to encounter a syntax error because the variable `str` is being declared twice within the same scope
 // interpret the error message and figure out why an error is occurring
 
 function capitalise(str) {
-  let str = `${str[0].toUpperCase()}${str.slice(1)}`;
-  return str;
+  let capitalisedStr = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return capitalisedStr;
 }
 
-// =============> write your explanation here
-// =============> write your new code here
+console.log(capitalise("hello"));

Sprint-2/1-key-errors/1.js

@@ -2,17 +2,17 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
+// An error will occur because the variable `decimalNumber` is being declared twice within the same scope
+
 
 // Try playing computer with the example to work out what is going on
 
 function convertToPercentage(decimalNumber) {
-  const decimalNumber = 0.5;
   const percentage = `${decimalNumber * 100}%`;
-
   return percentage;
 }
 
-console.log(decimalNumber);
+console.log(convertToPercentage(0.5));
 
 // =============> write your explanation here
 

Sprint-2/1-key-errors/2.js

@@ -4,17 +4,23 @@
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+// an error will occur because the value `3` has been put in the parentheses of the function.
 
-function square(3) {
+
+function square(num) {
     return num * num;
 }
+console.log(square(3));
 
 // =============> write the error message here
+// SyntaxError: Unexpected number
 
 // =============> explain this error message here
+// An error occurs because the function parameter `3` is a literal value instead of a variable name.
 
 // Finally, correct the code to fix the problem
 
+
 // =============> write your new code here