A binomial tree of order k is recursively defined as follows. A binomial tree of order 0 is a single node. A binomial tree of order k>0 consists of a root node and k children, where the ith child of the root is the root of a binomial tree of order i, 0sisk-l. A drawing of a binomial tree of order 4 is: Prove, using structural induction, that the number of nodes in a binomial tree of order k is 2. You must use structural induction to receive full credit for this