Please answer this question in Java, and use comments to explain. Thank you!

3. (10 points) Implement the Merge Sort algorithm in a recursive fashion. In other words, given any integer array, implement the static int[] MergeSort(int[] arr, int left, int right) method and the static int[] Merge(int[] left_arr, int[] right_arr) method. After MergeSort() is done executing, an array sorted in non-decreasing order should be returned in main()