2 Proof by Induction Consider recursive algorithm power(2, n) which computes 2\" for non-negative integer n: Algorithm powerset(A): If A = El return {ill} else do { pick a E A, set A' :2 A\\{a}, set P := powerset(A') let N :2 E), for all 5' E P, add set S U {a} as an element of N return P U N } Use induction to prove that for all sets A, algorithm powerset(A) returns the powerset of A, i.e. the set of all subsets of A