The following preparations are essential for any () of marine diesel engine before it may be started.
A. doing
B. make
C. turn
D. operating
查看答案
电网的电压质量取决于电力系统中无功功率的平衡,无功功率不足电网电压偏低。()
A. 正确
B. 错误
轴的转速不大于1500r/min时,弹性联轴器找中心,其周与端面允许偏差值不得超过()。
A. 0.06mm
B. 0.08mm
C. 0.10mm
D. 0.15mm