need help with C++ (ADT)

Problem 1 (10 points) Give the prefix, infix and postfix expressions corresponding to the following tree: (b A node in the binary tree in problems 2, 3 and 4 below is represented with the following data structure: struct Node \ int key Node *left, *righponters to the left and right children Problem 2 (20 points) Complete the code of a recursive function removeAllLeaves below that takes a pointer to the root node / remove the leaf nodes from a given tree and return a pointer to the root of the modified tree Node* removeAllLeaves(Node* root) \