(3%) The following question is a about a binary tree. Denote x as a node. The function parent(x) returns the parent of x. Furthermore, left(x) and right(x) return the left child and right child of node x, respectively. w and y are nodes of a binary tree which is shown below. left(parent(parent(right(w)))) is 5. right(right(parent(parent(y)))) is 9. What are w and y?