add formatTimeDisplay() answers explaining pad() calls and returning values

Author: Zadri415

Sprint-2/4-mandatory-interpret/time-format.js

@@ -18,17 +18,27 @@ function formatTimeDisplay(seconds) {
 
 // a) When formatTimeDisplay is called how many times will pad be called?
 // =============> write your answer here
+// Three 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 first time pad() run, its used for hours part of time.
+   Because 61 seconds equals 0 hours, the value given to num is 0. */
 // c) What is the return value of pad is called for the first time?
 // =============> write your answer here
+/* The first time pad() runs, it's formatting the hours part of time.
+Since the hours value is 0, it turns that into the string '00' by adding a leading zero before returning it. */
 
 // 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
+/* When the function runs with 61 seconds, the last time pad() is called is for the second part of the time.
+Since 61 seconds has 1 second left over after making a full minute, the value passed into pad() is 1.
+Inside the function, num equals 1, and it gets turned into '01' so the final time shows as 00:01:01. */
 
 // 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
+/* When pad() is called for the last time, num is 1 because there's 1 second left over.
+   The function turns that number into the string '01' by adding a leading zero.
+   That '01' is the value that gets returned and used as the seconds part of the final time display (00:01:01). */