Show that the powerset of A intersection B is equal to the powerset of A intersect the powerset of B.

a) P(A n B) = P(A) n P(B)
b) P(A n B) = P(A) u P(B)
c) P(A n B) = P(A) - P(B)
d) P(A n B) = P(A) + P(B)