Let (Xi)I be a family of sets, and A, B and C be sets. a) Let Xn = [0, 2 n ) for each n N +. (i) Find T {Xn|n N +}, and Prove your answer. (ii) Find S {Xn|n N +}, and Prove your answer. [5,5] b) Prove that B ( S {Xi |i I}) c = Bc T {Xc i |i I}. [4] c) Prove that if A4B = , then A = B