1. Write a recursive function int binarySearch(int[] a, int start, int end, int x) that uses the binary search algorithm to check whether the sorted array a contains the element x anywhere between indices start and end, inclusive. Function should return index of element 'x' if it exists in the array and return -1 otherwise. 2. Write a recursive function of MergeSort to sort an array in ascending order 3. Write a recursive function Sum that takes a two-dimensional array and returns sum of its all elements.