The guide shoes are secured to the crosshead by means of（）
A. through bolts
B. end chock bolts
C. side chock bolts
D. tap-bolt
流体在管路中的流动阻力分为直管阻力和局部阻力。
A. 正确
B. 错误
If the engine of a survival craft does not start，check to see（）.
A. that the fuel valve is open
B. if the air supply system is open
C. if the water sprinkler system is open
D. if the limit switch is o
典型的大陆性、海洋性气候应分布在哪些地区？为什么？
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