5. When we use the divide-and-conquer view on the mergesort and the quicksort, for which one, the divide step is more expensive (in the sense of computing time) than the combine step? (a) mergesort (b) quicksort 15. To recover the array 23,17,14,6,13,10,1,5,7,12 to a max-heap, how many swap operations do you need? Ans: 16. Given a max-heap whose values correspond to the array indices from 1 through n, what is the smallest possible index for a node with height 2 in the heap? Ans