Step-by-step explanation:
The height of the tree can be defined as the number of levels in the tree.Suppose if there are 45 levels in the tree then the height of the tree will be 45.
If there is only root node in the tree means there is only one level in the tree then the height of the tree is 1.
Or we can also define it as the depth of the node that is deepest or root node's height.