A power plant in California uses coal at a rate of 100,000 pounds per day. It also uses MRO material at a rate of 1,000 pounds per day. Carbon costs $0.01 per pound, while MRO material costs $10 per pound, on average. The maintenance cost at the power plant is 25 percent.

TRAIN: Delivery time = 15 days Carload (100,000 pounds) at $400 per car Full train (70 cars) at $15,000 per train

TRUCK: Delivery time = 4 days Minimum cost = $100 Up to 10,000 pounds at $0.08 per pound Between 10,000 and 20,000 pounds at $0.07 per pound per full load Between 20,000 and 40,000 pounds at $0.06 per pound per full load Small TL (40,000 pounds) for $2,000 large TL (60,000 pounds) for $2,600

Safety inventory of coal and MRO materials is maintained at double consumption during the supply lead time. What mode of transportation do you recommend for each of the two products? Because?