2. 7 points The probabilities for A1=.2, A2 = .5 and A3 = .3. The probability P(B | A1) = .5, P(B | A2) = .4, and P(B | A3) = .3 . a. Compute P( B 1 ), P( B 2 ), and P( B 3 ). b. Apply Baye's theorem to compute the posterior probabilty P (A2 | B). c. Use the tabular approach to apply Baye's theorem to computer P (A1 | B), P (A2 | B), and P (A3 | B)