液压举升油路中,()的作用是控制动臂油缸下降速度的。
参考答案:限速阀
A large number of new schools __________ to help those left-behind children next year.
A.will build
B.will be built
C.were built
D.are built
覆冰区段,与110kV线路LGJ-240/30导线配合的镀锌绞线最小标称截面不小于:()
A.35mm2
B.50mm2
C.80mm2
D.100mm2