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A typical coal-fired power plant burns 300 metric tons of coal every hour to generate 2.7 × 106 MJ of electric energy, 1 metric ton = 1000 kg; 1 metric ton of coal has a volume of 1.5 m3. The heat of combustion of coal is 28 MJ/kg. Assume that all
a. Suppose the coal is piled up in a 10 m × 10 m room. How tall must the pile be to operate the plant for one day?
b. What is the power plant's efficiency?
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