17. The distribution system for the Herman Company consists of three plants, two warehouses, and four customers. Plant capacities and shipping costs per unit (in $) from each plant to each warehouse are as follows: Warehouse Plant 1 2 Capacity 123 4 7 450 8 5 600 3 5 6 380 Customer demand and shipping costs per unit (in $) from each warehouse to each cus- tomer are Customer Warehouse 1 2 6 4 2 3 6 Demand 300 300 H 3 8 4 7 7 300 400 a. Develop a network representation of this problem. b. Formulate a linear programming model of the problem. c. Solve the linear program to determine the optimal shipping plan.