Work was done earlier but had computer troubles!

exercises.js

@@ -5,6 +5,13 @@
  * @return {string} reversed
  * ie: "cat" => "tac"
  */
+var firstReverse = function(str){
+    if(typeof str != 'string'){
+        return null;
+    }
+    else
+        return str.split('').reverse().join('');
+};
 
  /** Function: alphaOrder
  * The function will take the str parameter being passed in and
@@ -13,6 +20,13 @@
  * @return {string} in alphabetical order
  * ie: "cake" => "acek"
  */
+var alphaOrder = function(str){
+    if(typeof str === 'string'){
+        return str.split('').sort().join('');
+    }
+    else
+        return null
+}
 
  /** Function: vowelCount
  * The function will take the str parameter being passed in and
@@ -21,6 +35,22 @@
  * @return {number} count of vowels
  * ie: "oreo" => 3
  */
+var vowelCount = function(str){
+    var vowels = ['a','e','i','o','u'];
+    var count = 0;
+
+    if(typeof str !== 'string'){
+    return null;
+    }
+
+    for(var i = 0; i< str.length; i++){
+
+        if(vowels.includes(str[i])){
+        count++
+    }
+}
+    return count;
+}
 
  /** Function: timeConvert
  * The function will take the str parameter representing the amount of minutes being passed in and
@@ -31,6 +61,16 @@
  * ie: 68 => 1:8
  */
 
+ var timeConvert = function(num){
+    var minutes = num%60;
+    var hours = Math.floor(num/60);
+
+    if(typeof num === 'number')
+        return hours + ':' + minutes;
+    else
+     return null;
+ }
+
  /** Function: repeatString
  * The function will take in two parameters and repeat a given string (first argument)
  * num times (second argument). Return an empty string if num is a negative number
@@ -39,7 +79,15 @@
  * @return {string} repeated num times
  * i.e repeatString("money", 3) => "moneymoneymoney".
  */
+var repeatString = function(str,num){
+    if(num > 0){
+        return str.repeat(num);
+    }
+    else
+    return null;
+
 
+}
 
 /**
  * Below here we see a module.exports which is set to an object with a bunch of keys.
@@ -56,9 +104,9 @@
  */
 
 module.exports = {
-    firstReverse: null,
-    alphaOrder: null,
-    vowelCount: null,
-    timeConvert: null,
-    repeatString: null
+    firstReverse: firstReverse,
+    alphaOrder: alphaOrder,
+    vowelCount: vowelCount,
+    timeConvert: timeConvert,
+    repeatString: repeatString
 }