State University must purchase 1,100 computers from three vendors. Vendor 1 charges 500 per computer plus a delivery charge of5,000. Vendor 2 charges 350 per computer plus a delivery charge of4,000. Vendor 3 charges 250 per computer plus a delivery charge of6,000. Vendor 1 will sell the university at most 500 computers; vendor 2, at most 900; and vendor 3, at most 400. Formulate an IP to minimize the cost of purchasing the needed computers.