Let X be the set of alternatives. A choice function C satisfies menu union property if for each pair A, A'C X such that ANA' = 0, C(AU A') = C(A)UC(A'). Let C satisfy menu union. (a) Show that C(A' U.UA*) =C(A')U..UC(A*) for any pairwise disjoint sets A', A,. A*. (b) Does C satisfy WARP? Show.