Nash Auto has two plants, two warehouses, and three customers. The plants are in Detroit and Atlanta, the warehouses are in Denver and New York, and the customers are in Los Angeles, Chicago, and Philadelphia. Cars are produced at plants, then shipped to ware-houses, and finally shipped to customers. Detroit can produce 200 cars per week, and Atlanta can produce 160 cars per week. Los Angeles requires 80 cars per week, Chicago requires 70, and Philadelphia requires 60. It costs $8000 to produce a car at each plant. The costs of shipping a car between various cities are listed in the file P05_56.xlsx. Assume that during a week, at most 75 cars can be shipped from a warehouse to any particular city. Determine how to meet Nash’s weekly demands at minimum cost.