Comment fix

Author: sadanandpai

challenges/primitives.md

@@ -53,11 +53,11 @@ typeof Symbol()           //   "symbol"
 typeof [1, 2]             //   "object"
 typeof {}                 //   "object"
 
-typeof NaN                //   "number"        // NaN is Not a Number
-typeof undeclaredVar      //   "undefined"     // undeclaredVariable is never declared
-typeof Infinity           //   "number"        // Infinity, -Infinity, -0 are all valid numbers in JavaScript
-typeof null               //   "object"        // This stands since the beginning of JavaScript
-typeof /regex/            //   "object"        // regular expressions start and end with '/' in literal form
+typeof NaN                //   "number"        (NaN is Not a Number)
+typeof undeclaredVar      //   "undefined"     (undeclaredVariable is never declared)
+typeof Infinity           //   "number"        (Infinity, -Infinity, -0 are all valid numbers in JavaScript)
+typeof null               //   "object"        (This stands since the beginning of JavaScript)
+typeof /regex/            //   "object"        (regular expressions start and end with '/' in literal form)
 ```
 
 ###### Notes