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In some countries, liquid nitrogen is used on dairy trucks instead of mechanical refrigerators. A 3.00-hour delivery trip requires 200 L of liquid nitrogen, which has a density at
(a) Calculate the heat transfer necessary to evaporate this amount of liquid nitrogen and raise its temperature to
(b) What is this heat transfer rate in kilowatt−hours?
(c) Compare the amount of cooling obtained from melting an identical mass at
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