If U = {1, 2, 3, 4, 5, 6, 7, 8, 9 }, A= {2, 4, 6, 8} and B = { 2, 3, 5, 7}. Verify that (i) (A ∪ B)' = A' ∩ B' (ii) (A ∩ B)' = A' ∪ B'