As a general response to this question, here's the time reference table for the different sorts:

Sort	Worst Case	Average Case
Selection Sort	N2	N2
Bubble Sort	N2	N2
Insertion Sort	N2	N2
Mergesort	N*Log2N	N*Log2N
Quicksort	N2	N*Log2N
Radix Sort	N	N
Tree Sort	N2	N*Log2N
Heap Sort	N*Log2N	N*Log2N

It really depends on how well the data is presorted.

If it is sorted, bubble sort can be as efficient as O(N), but it is usually O(N²).

The worst case for a quick sort is just the opposite. If the data is already sorted and the smallest item is chosen as the pivot, time can be O(N²), but for most data sets it's (NlogN).

C-.