Samples of a cast aluminum part are classified on the basis of surface finish and edge finish. The results of 100 parts are summarized as follows. Edge finish Surface finish Excellent Good Excellent 75 15 Good 4 6 Let A denote the event that a sample has excellent surface finish, and let B denote the event that a sample has excellent edge finish. If a part is selected at random, determine the following probabilities: (a) P(AB), (b) P(AUB) and (c) P(A'UB)