Assume that the energy contained in coal is about 10,000 Btu/lbm. An electrical power plant burning coal has an output capacity of 1200 MW and the plant converts about 30% of the input energy to electricity. How many short tons of coal are required by this plant per year, assuming it operates continuously? If 10% of the coal mass remains as residual ash, how many tons will develop in the ash pile over 25 years?