A local supermarket has three checkout counters Two customers arrive at the counters at different times when the counters are serving no other customers Each customer chooses a counter at random, independently of the other: Let Y1 denotes the number of customers who choose counter 1 and Yz the number who select counter 2. The joint probability function of Y1 ad Yz is as follows: Y1-0 Y1-1 Y1= 2 Y2-0 1/9 2/9 1/9 Y2-1 2/9 2/9 Y2-2 1/9 a) Compute E(Y1) and E(Y2): b) Compute E(Y1/Y2-1) c) Compute Pr (Y1) and Pr (Yz) (Hint: Marginal Probability Distribution) d) Compute Pr(Y1-OY2-1) and Pr(Y1-1Y2-1)