Please need this as soon as posible!!

9 [4 points] Write a recursive function int max key (node *ptr) which takes as argument the pointer to the root of a binary tree and returns the maximum of key values. Assume that the keys are distinct. 10 [5 points] What is the worst-case time (in Big-o) for building a Min-Heap of N nodes by repeated insertion of nodes - one at a time? Justify your answer. 11 [6 points] Given a Min-Heap represented by an array HO .. M with N keys stored in H[1 ...M], write a function deleteMin which takes H and N as arguments, and performs the delete-min operation (and maintains the Heap property)