Wheat is harvested at farms in Nebraska and Colorado before being shipped to the three grain elevators in Kansas City, Omaha, and Des Moines. The amount of wheat harvested at each farm is 300 tons. The wheat is then shipped from grain elevators to the mills in Chicago, St. Louis, and Cincinnati. Each mill demands the following number of tons of wheat: Chicago - 200. St. Louis - 100, and Cincinnati - 300. The unit shipping cost (i. e., cost per ton) between points are given in the table below. The maximum capacities of the three grain elevators are: Kansas City - 160, Omaha - 185. Des Moines - 285.Create a model to determine the best shipment plan, which meets all requirements and minimizes the total shipment cost.