(a) Insert the following sequence of elements into a threaded binary search tree, starting with an empty tree: 11, 20, 15, 25, 35, 16, 17, 19 and write a program for preorder traversal. (b) Create the graph with 6 nodes and 7 edges and perform the DFS and BFS traversals and which data structure is being used in each traversal. Can you perform pre-order traversal of this graph or not and justify