Please solve this question. This is related to recursion and induction. You may use 'base case', 'step case'. Thank you so much!

EExercise 124. This exercise is concerned with defining a mathematical entity of binary trees that corresponds to the BTree class. We refer to such a tree as a binary tree with labels from a set S, and use B Treess for the set of all these trees. (a) Give a definition, similar to Definition 48, of a mathematical entity of binary trees which corresponds to the B Tree class. (b) Recursively define an operation that takes two binary trees and returns a binary tree where the second argument has been added below the right-most leaf of the tree. (c) Write code which implements the operation from the previous part. Definition 48: tree A full binary tree with labels from a set S is given by Base case tree. For every element s of S there is a tree, trees, consisting of just one node labelled with the element s. Step case tree. Given two trees t and t' labelled over S, and an element s of S, there is a tree trees(t, t'). EExercise 124. This exercise is concerned with defining a mathematical entity of binary trees that corresponds to the BTree class. We refer to such a tree as a binary tree with labels from a set S, and use B Treess for the set of all these trees. (a) Give a definition, similar to Definition 48, of a mathematical entity of binary trees which corresponds to the B Tree class. (b) Recursively define an operation that takes two binary trees and returns a binary tree where the second argument has been added below the right-most leaf of the tree. (c) Write code which implements the operation from the previous part. Definition 48: tree A full binary tree with labels from a set S is given by Base case tree. For every element s of S there is a tree, trees, consisting of just one node labelled with the element s. Step case tree. Given two trees t and t' labelled over S, and an element s of S, there is a tree trees(t, t')