4 Retailing Problem 4. Retailing. A retailer has shelf space for 4 perishable items that are destroyed at the end of the day if unsold. The unit cost per item stocked is $3.00, while the selling price is $6.00. The probabilities of demand are: Pr(D = 0) = 0.1, Pr(D = 1) = 0.3, Pr(D = 2) = 0.3, Pr(D = 3) = 0.2, Pr(D = 4) = 0.1. a. What is the mean number of items demanded? b. Suppose the retailer stocks exactly 2 items. What is her expected profit? c. Suppose the retailer stocks exactly 2 items. What is the standard deviation of her profit