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问题 单项选择题

把下面的六个图形分为两类，使每一类图形都有各自的共同特征或规律，分类正确的一项是（）

A.①③④，②⑤⑥

B.①②⑤，③④⑥

C.①③⑥，②④⑤

D.①④⑤，②③⑥

答案

参考答案：A

单项选择题

What is TRUE about hoisting operations（）.

A.Personnel may work beneath suspended loads，as long as they are alert and wear hard hats

B.If a suspended load with no tag begins to spin，personnel should attempt to stop the spinning if the load is within reach

C.If tag lines are used to control a suspended load，they should be secured to the deck

D.Personnel not involved in the hoisting operation should be kept clear of the transfer area
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单项选择题

消防喷淋报警阀应逐个进行渗漏试验。试验压力应为额定工作压力的（）倍，试验时间应为5min，阀瓣处应无渗漏。

A、1

B、1.5

C、2

D、1.15
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