An appliance company has two warehouses and two retail outlets. Warehouse A has 400 refrigerators, and warehouse B has 300 refrigerators. Outlet I needs 200 refrigerators, and outlet II needs 300 refrigerators. It costs $36 to ship a refrigerator from warehouse A to outlet I and $30 to ship a refrigerator from warehouse A to outlet II. It costs $30 to ship a refrigerator from warehouse B to outlet I and $25 to ship a refrigerator from warehouse B to outlet II. How should the company ship the refrigerators to minimize the cost?