航行中的螺旋桨故障主要有()。Ⅰ.振动;Ⅱ.鸣音;Ⅲ.失去平衡;Ⅳ.桨叶折断;Ⅴ.桨叶穴蚀。
A.Ⅱ+Ⅲ
B.Ⅰ+Ⅱ+Ⅳ+Ⅴ
C.Ⅲ+Ⅳ+Ⅴ
D.Ⅰ+Ⅱ+Ⅲ+Ⅳ
参考答案:A
《职业病防治法》中所称用人单位是指()。
A.企业、事业单位、政府机关
B.企业、科研单位、政府机关
C.企业、事业单位和个体经济组织等
“We ______ other possibilities too, such as murder. We ______ until we find convincing evidence.”said Detective Sam Peterson.
A. had looked at; wouldn’t give up B have looked at; don’t give up
C have considered; haven’t given up D. have been looking at; won’t give up