Which of the following statements related to efficiencies for cyclic devices iscorrect? The Carnot efficiency for heat engines is equal to 1. The COP of a refrigerator cannot be greater

than 1. It is possible to design a heat engine whose efficiency is greater than that of a Carnot heat engine. The COP of reversible heat pumps is greater than that of reversible refrigerators if both devices operate between the same hot and cold temperatures.

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