consider the following instance variable and method. what is returned by the call mystery (0, arr.length − 1, num) ? (a) the number of elements in arr that are less than num (b) the number of elements in arr that are less than or equal to num (c) the number of elements in arr that are equal to num (d) the number of elements in arr that are greater than num (e) the index of the middle element in arr
