​A Company Ships Products from Four Factories to Four Warehouses

​A company ships products from four factories to four warehouses. The factory capacities, warehouse requirements, and per-unit shipping costs are shown below:
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How many products should the company ship from each factory to each warehouse to minimize monthly shipping costs? What will the monthly shipping cost be if the shipping plan is followed? (Use the minimum cost method to find an initial feasible solution and the transportation simplex method to find an optimal solution.)