How do I solve this problem in excel? Please show me how to do it, your help is greatly appreciated. Thumbs up guaranteed for best answer :)

The Grand Prix Automobile Company manufactures automobiles in three plants and then ships them to four regions of the country. The plants can supply the amounts listed in the right column of the input data. The customer demands by region are listed along the bottom row of the input data and the unit costs of shipping an automobile from each plant to each region are listed in the middle of the input data. Grand Prix wants to find the lowest cost shipping plan for meeting the demands of the four regions without exceeding the capacities of the plants. (NOTE: for full credit, use the solution structure for a network model.) Plant 1 Plant 2 Plant 3 Demand Region 1 $131 $250 $178 450 Customer Regions Region 2 Region 3 $218 $266 $116 $263 $132 $122 200 300 Region 4 $120 $278 $180 300 Capacity 450 600 500