As county engineer, it is your responsibility to design a master plan for refuse disposal for a 4-city area. All waste is delivered to one of two transfer stations where it is compacted and placed into large transport vehicles for shipment to one of three landfills. Each transfer station can process 700 tons of refuse daily, and the capacities of the three landfills are 500, 420, and 600 tons of waste per day, respectively. All shipping costs are directly proportional to the travel distances shown in the table below, but shipments from the transfer stations are 50% lower per mile than are those of the route trucks that transport refuse directly from residence to transfer station:

For example, a unit of refuse transported by route truck from Pleasantville to Transfer Station Number 1 travels a distance of 45 miles. If that unit of refuse is then transported to Landfill No. 3. it will be moved another 146 miles but at a 50% lower unit transport cost. Pleasantville generates 205 tons of waste each day. and Landfill No. 3 can process a total of 600 tons per day from both transfer stations.

Formulate a linear program that will help you plan a policy for managing the disposal operation at least cost.