Question: The distribution system for a company coXnsists of two plants, three warehouses and three customers. Plant capacities and shipping costs per unit (in $) from each plant to each warehouse are as follows:

Customer demand and shipping costs per unit (in $) from each warehouse to each customer are

Due to technical reasons items can not be shipped from Warehouse-1 to Customer-2 temporarily. In addition, direct shipments can be made from Plant-1 to Customer-1 at a cost of $4 per unit and from Plant-2 to Customer-3 at a cost of $2 per unit. Draw a network representation and formulate a linear programming model for this problem.