Assume that we want to apply mergesort to sort the array A with 5 elements where the initial values of the array elements (from A[1] to A[5]) are A : 19 16 13 25 22 . How many times do we push an activation record (for mergesort or merge) onto the runtime stack before the completion of the algorithm? Note that mergesort(A, 1, 5) is the rst activation record pushed onto the runtime stack.