fix(curriculum): update code order to help with confusion (#48366)

* minor - update order to help with confusion

* update variable names, remove source from tests

* minor - wording

* missing variable rename

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-with-the-rest-parameter-to-reassign-array-elements.md

@@ -27,20 +27,24 @@ Variables `a` and `b` take the first and second values from the array. After tha
 
 # --instructions--
 
-Use destructuring assignment with the rest parameter to perform an effective `Array.prototype.slice()` so that `arr` is a sub-array of the original array `source` with the first two elements omitted.
+Use a destructuring assignment with the rest parameter to emulate the behavior of `Array.prototype.slice()`. `removeFirstTwo()` should return a sub-array of the original array `list` with the first two elements omitted.
 
 # --hints--
 
-`arr` should be `[3,4,5,6,7,8,9,10]`
+`removeFirstTwo([1, 2, 3, 4, 5])` should be `[3, 4, 5]`
 
 ```js
-assert(arr.every((v, i) => v === i + 3) && arr.length === 8);
+const testArr_ = [1, 2, 3, 4, 5];
+const testArrWORemoved_ = removeFirstTwo(testArr_);
+assert(testArrWORemoved_.every((e, i) => e === i + 3) && testArrWORemoved_.length === 3);
 ```
 
-`source` should be `[1,2,3,4,5,6,7,8,9,10]`
+`removeFirstTwo()` should not modify `list`
 
 ```js
-assert(source.every((v, i) => v === i + 1) && source.length === 10);
+const testArr_ = [1, 2, 3, 4, 5];
+const testArrWORemoved_ = removeFirstTwo(testArr_);
+assert(testArr_.every((e, i) => e === i + 1) && testArr_.length === 5);
 ```
 
 `Array.slice()` should not be used.
@@ -55,7 +59,7 @@ Destructuring on `list` should be used.
 assert(
   __helpers
     .removeWhiteSpace(code)
-    .match(/\[(([_$a-z]\w*)?,){1,}\.\.\.arr\]=list/i)
+    .match(/\[(([_$a-z]\w*)?,){1,}\.\.\.shorterList\]=list/i)
 );
 ```
 
@@ -64,23 +68,25 @@ assert(
 ## --seed-contents--
 
 ```js
-const source = [1,2,3,4,5,6,7,8,9,10];
 function removeFirstTwo(list) {
   // Only change code below this line
-  const arr = list; // Change this line
+  const shorterList = list; // Change this line
   // Only change code above this line
-  return arr;
+  return shorterList;
 }
-const arr = removeFirstTwo(source);
+
+const source = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+const sourceWithoutFirstTwo = removeFirstTwo(source);
 ```
 
 # --solutions--
 
 ```js
-const source = [1,2,3,4,5,6,7,8,9,10];
 function removeFirstTwo(list) {
-  const [, , ...arr] = list;
-  return arr;
+  const [, , ...shorterList] = list;
+  return shorterList;
 }
-const arr = removeFirstTwo(source);
+
+const source = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+const sourceWithoutFirstTwo = removeFirstTwo(source);
 ```