测量液位用的差压计，其差压量程（）.
A.由介质密度决定与封液密度无关
B.由封液密度决定，与介质密度无关
C.两者都有关
D.两者都无关
参考答案：A
概述《三国演义》中“七擒七纵”的前因后果。
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When lowering manropes alongside a stage rigged over the side of a vessel，they should be allowed to trail in the water（）.
A.to easily remove the kinks that form in the lines
B.to allow the seamen on the stage to know the direction and strength of the current
C.to provide the seaman something to hold onto if he or she falls from the stage into the water
D.only for short periods of time since they will become waterlogged and be very heavy to pull up
