A company manufactures widgets at two factories, one in Memphis and one in Denver. The Memphis factory can produce up to 150 widgets per day, and the Denver factory can produce up to 200 widgets per day. The company are shipped by air to customers in Los Angeles and Boston. The customers in each city require 130 widgets per day. Because of the deregulation of airfares, the company believes that it might be cheaper to first fly some widgets to New York or Chicago and then fly them to their final destinations. The costs of flying a widget are shown in the file P05_53.xlsx.

a. Determine how to minimize the total cost of shipping the required widgets to the customers.

b. Suppose the capacities of both factories are reduced in increments of 10 widgets per day. Use SolverTable to see how much the common reduction can be before the total cost increases, and how much it must be before there is no feasible solution.