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【单选题】第二篇 Sleep We all know that the normal human daily cycle of activity is of some 7 - 8 hours’ sleep alternating with some 16 - 17 hours’ wakefulness and that, broadly speaking, the sleep n...
A.
people hate the inconvenience of working on night shifts.
B.
your life is disturbed by changing from day to night routines and back.
C.
not all industries work at the same hours.
D.
it is difficult to find a corps of good night workers.
【单选题】现有两种高聚物A、B，A能溶于氯仿等有机溶剂，B不溶于任何溶剂，加热不会变软或熔融，则下列叙述中不正确的是（ ）
A.
高聚物A可能具有弹性，而高聚物B一定没有弹性
B.
高聚物A一定是线型高分子化合物材料
C.
高聚物A一定是体型高分子化合物材料
D.
高聚物B一定是体型高分子化合物材料