A regional airline can buy its jet fuel from any one of three vendors. The airline's needs for the upcoming month at each of the three airports it serves are 100000 gal at airport 1, 180000 gal at airport 2, and 350 000 gal at airport 3. Each vendor can supply fuel to each airport at a price (in cents per gallon) given by the following schedule: Airport 1 Airport 2 Airport 3 Vendor 1 92 89 90 Vendor 2 91 91 95 Vendor 3 87 90 92 Each vendor, however, is limited in the total number of gallons it can provide during any one month. These capacities are 320000 gal for vendor 1, 270000 gal for vendor 2, and 190000 gal for vendor 3. Determine a purchasing policy that will supply the airline's requirements at each airport at minimum total cost.