add code and explanations

Author: Dipa-Sarker

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

@@ -1,13 +1,22 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// The variable inside the function str has already declared as function parameter.
 
 // call the function capitalise with a string input
 // 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;
-}
+//function capitalise(str) {
+  //let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+  //return str;
+//}
 
 // =============> write your explanation here
+// Repeatative variable declaration prediction matches with the error message. Then I changed the old variable into new inside the 
+// function. Then affter running the code it won't return anything cause no function call has been made yet.
 // =============> write your new code here
+// This is my code:
+function capitalise(str) {
+  let newstr = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return newstr;
+} 
+console.log(capitalise("dipa"));

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

@@ -2,19 +2,37 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
+// I thought the function will work properly but couldn't print the correct value cause the value should be convertToPercentage 
+// but it is declared only as decimalNumber.
 
 // Try playing computer with the example to work out what is going on
 
-function convertToPercentage(decimalNumber) {
-  const decimalNumber = 0.5;
-  const percentage = `${decimalNumber * 100}%`;
+//function convertToPercentage(decimalNumber) {
+  //const decimalNumber = 0.5;
+  //const percentage = `${decimalNumber * 100}%`;
 
-  return percentage;
-}
+  //return percentage;
+//}
 
-console.log(decimalNumber);
+//console.log(decimalNumber);
 
 // =============> write your explanation here
+// When I run the code after my prediction it shows SyntaxError: Identifier 'decimalNumber' has already been declared. Which means
+// decimalNumber has been declared already as function parameter and then again declared inside the function as variable. Then when I 
+// declare const decimalNumber = 0.5; outside the function and run the code it shows the value of variable decimalNumber which is 0.5. Then
+// I replace console.log(decimalNumber); to console.log(convertToPercentage); and run the code again and it shows this output 
+// [Function: convertToPercentage] which means only the funtion name. Then I replace console.log(convertToPercentage); to
+// console.log(convertToPercentage(decimalNumber)); again and it finally works properly that means converted the decimal number to 
+// percentage value which shows 50% . 
+
 
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+// Corrected code:
+
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+  return percentage;
+}
+const decimalNumber = 0.5;
+console.log(convertToPercentage(decimalNumber));

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

@@ -4,17 +4,28 @@
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+// I think we cannot directly insert value which is 3 as a parameter. We have to declare it as a variable. 
 
-function square(3) {
-    return num * num;
-}
+//function square(3) {
+//  return num * num;
+//}
 
 // =============> write the error message here
+// The error message shows SyntaxError: Unexpected number
 
 // =============> explain this error message here
+// The error shows SyntaxError as Unexpected number which means the function syntax doesnot expect to input
+// any values directly in the parameter. That's why the function doesnot work. 
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
+// The correct code: 
+
+function square(num) {
+    return num * num;
+}
+let num = 3;
+console.log(square(num));