Write a method called isFull that returns true if a binary tree is full and false if

Question:

Write a method called isFull that returns true if a binary tree is full and false if it is not. A full binary tree is one in which every node has 0 or 2 children. For example, reference trees #1 and #2 are not full, but #3 is full. By definition, the empty tree is considered full.

Reference Tree #2 2 Reference Tree #1 1 7. 4 4 Reference Tree #3 2 3 8. 9. 3. 1.