Assume this tree on the right is a binary search tree even though you cannot see what the keys and values are at the nodes (the letters we write below are just ames" for the nodes for the purpose of answering the questions).

a) Is the tree an AVL tree?

b) If we remove only node H, is the result an AVL tree?

c) If we remove only node J, is the result an AVL tree?

d) If we remove only node K, is the result an AVL tree?