Allied Freight supplies goods to three customers, who each require 30 units. The company has two ware-houses. In warehouse 1, 40 units are available, and in warehouse 2, 30 units are available. The costs of shipping one unit from each warehouse to each customer are shown in the file P05_67.xlsx. There is a penalty for each unsatisfied customer unit of demand—with customer 1, a penalty cost of $90 is incurred; with customer 2, $80; and with customer 3, $110.

a. Determine how to minimize the sum of penalty and shipping costs.

b. Use SolverTable to see how a change in the unit penalty cost of customer 3 affects the optimal cost.

c. Use SolverTable to see how a change in the capacity of warehouse 2 affects the optimal cost.