1. Given the array [2 5 -1 9 4 0 -3 7 3 6 -6], describe the steps for the following sorting algorithms:

a) Merge sort;

b) Quick sort;

c) Heap sort.

2. Please generate an array with 12 elements, which is the worst case for the first iteration of QUICKSORT algorithm and then is the best case for the second iteration of QUICKSORT algorithm (The first element is used as Pivot). Please explain why your answer is the worst case and the best case for the first and second iterations.

3. Given the following list of positive integers, use radix sort to sort them in an increasing order: 439 45 234 91 649 932 47 829 48 732 843 236 727 462 828 999 619 503 290 83 439 545 9 475 683 889 497