Solve the questions (1626) based on the following Tree: (16) The number of children of the root node is: (17) The number of internal nodes is: (18) The leaves nodes are: (19) The siblings of the G node are: (20) The parent of the L node is: (21) The number of the external nodes is: (22) The children of the M node are: (23) The ancestors of the E node are: (24) The depth of the H node is: (25) The height of the N node is: (26) When calling postorder(Tree, P), the order of the visited nodes is: 5pts