For this question, you are to implement a method called getSize that takes first node in a binary tree (its root) and returns the number of nodes in the tree. public c l a s s BinaryNode { p r i v a t e BinaryNode l e f t , r i g h t ; p r i v a t e T element ; public BinaryNode (T elem) { l e f t = r i g h t = n u l l ; element = elem ; } public BinaryNode g e tLe f t ( ) { r e turn l e f t ; } public void setLeft (BinaryNode node ) { l e f t = node ; } public BinaryNode ge tRight ( ) { r e turn r i g h t ; } public void setRight (BinaryNode node ) { l e f t = r i g h t ; } public T getElement ( ) { r e turn element ; } public void setElement (T elem) { element = elem ; } }