1. Please mark which topics are covered in the reading assignment for today:
(a) binary trees (Y/N)
(b) heap sort (Y/N)
(c) inorder, preorder, and postorder (Y/N)
(d) graphs (Y/N)
2. Show, step by step, how insertion sort, quick sort, and merge sort will sort a list consisting of elements 4, 21, 2, and 9. No code is needed.