On a 20 ft cantilever beam, Load W1=200 or W2=500 or both may be applied at the midpoint B or at the end of the beam C. The bending moment induced at th fixed support A, MA, will depend on the magnitude of the loads at B and C. E1 = MA < 5,000 E2 = 1,000 <= MA < 12,000 E3 = MA {2000, 7000} P(W1 at B) = 0.25 P(W1 at C) = 0.6 P(W2 at B) = 0.3 P(W@ at C) = 0.5 a.) Assuming the position of W1 and W2 are statistically independent, what are the respective probabilities with each of the possible values of MA? b.) Determine the probabilities: E1, E2, E3, E1nE2, E1UE2, E2'