For this problem, you may want to review set theory from CSE 20, especially the size of power set of a set. (6 points) Let n be a positive integer and define [n] to be the set of the first n positive integers. That is, n] 1,2,3,.. .,n]. We want to select two disjoint subsets A, B of [n]. In how many ways can we do this? Optional.) Now we want to select three subsets A, B, C of [n] such that AC C, B C C, and AnB-. In how many ways can we do this?