Nike Corp. supplies its four retail outlets from its four plants. The shipping cost per shipment from each plant to each retail outlet is given below. Unit Shipping Cost Retail Outlet Plant 1 2 3 4 1 $700 $800 $500 $200 2 $200 $900 $100 $400 3 $400 $500 $300 $100 4 $200 $100 $400 $300 Plants 1, 2, 3 and 4 make 10, 20, 20, and 10 shipments per month, respectively. Retail outlets 1, 2, 3, and 4 need to receive 20, 10, 10, and 20 shipment per month, respectively. The distribution manager now wants to determine the best plan for how many shipments to send from each plant to the respective retail outlets each month. The manager’s objective is to minimize the total shipping cost

a. formulate this problem on a spreadsheet and use Solver to find an optimal solution.