Problem
Canberra Freight is in charge of transporting auto parts for a US car manufacturer in Australia. Every week a tractor and one or two trailers move from the port of Melbourne to a warehouse located 430 km away. A tractor costs $75 per day, a trailer $30, a driver $7.5 per hour while running costs are $0.75 per kilometer. A trailer can contain 36 pallets. Derive the transportation cost per pallet as a function of shipment size for the case where one or two trailers are used.