A.一个动滑轮
B.一个定滑轮
C.一根杠杆
D.一个定滑轮和一个动滑轮组成的滑轮组
答案:C
----- How is business?
--- so, you know in warm weather, fruit ____ long.
A doesn’t keep B is not kept C is not keeping D can’t be kept
在HSE管理体系中,一般不符合项是指能使体系运行出现系统性失效或区域性失效的问题。