Reconsider Prob. 2–56E. Using appropriate software, study the effects of the unit cost of energy, the new combustion efficiency on the annual energy, and cost savings. Let the efficiency vary from 0.7 to 0.9, and let the unit cost vary from $12 to $14 per million Btu. Plot the annual energy and cost savings against the efficiency for unit costs of $12, $13, and $14 per million Btu, and discuss the results.
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