4. Answer the following questions for the keys 15, 26, 8, 11, 30, 7, 21, 9, 4, 18, 5 a. Draw the final structure of binary search tree T when above keys are inserted from left to right b. Draw the tree that results after successively executing the following functions TREE-DELETE (T,4), TREE-DELETE(T,8), TREE-DELETE(T,16)