单选题某蒸气压缩制冷循环，向冷凝器放热200kJ／kg，消耗外界功50kJ／kg，其制冷系数为（）。（A0.75B1.33C3D4
单选题
某蒸气压缩制冷循环，向冷凝器放热200kJ／kg，消耗外界功50kJ／kg，其制冷系数为（）。（
A
0.75
B
1.33
C
3
D
4
参考解析
解析：
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