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问题 单项选择题

若截面2处速度水头和截面1处速度水头相同，截面2处位置水头小于截面1处位置水头，则截面2的压力水头（）截面1的压力水头。

A.小于

B.大于

C.等于

D.A或B或C

答案

参考答案：D

单项选择题

2008年6月6日，8炼油厂油罐区的2号汽油罐发生火灾爆炸事故，造成1人死亡、3人轻伤，直接经济损失420万元。该油罐为拱顶罐，容量200m3。油罐进油管从罐顶接入罐内，但未伸到罐底。罐内原有液位计，因失灵已拆除。2008年5月20日，油罐完成了清罐检修。6月6日8时，开始给油罐输油，汽油从罐顶输油时进油管内流速为2.3～2.5m/s，导致汽油在罐内发生了剧烈喷溅，随即着火爆炸。爆炸把整个罐顶抛离油罐。现场人员灭火时发现泡沫发生器不出泡沫，匆忙中用水枪灭火，导致火势扩大。消防队到达后，用泡沫扑灭了火灾。事故发生后，在事故调查分析时发现，泡沫灭火系统正常，泡沫发生器不出泡沫的原因是现场人员操作不当，开错了阀门。该厂针对此次事故暴露出的问题，加强了员工安全培训，在现场增设了自动监控系统，完善了现场设备、设施的标志和标识，制订了安全生产应急救援预案。根据以上场景，回答问题(共16分，每题2分，前三题为单选题，后五题为多选题)：根据《生产安全事故报告和调查处理条例》，该起事故属于（）。

A.一般事故

B.较大事故

C.重大事故

D.特大事故

E.特别重大事故
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单项选择题

(Ⅰ)

In the dining room of my grandfather’ s house stood his heavy clock. Meals in the dining room were a (21) for our four generations to become one. My grandfather’ s clock always stood like a trusted old family friend, (22) us playing jokes and tellingstories, which was already a (23) of our life.

When I was a child, the old clock interested me. I watched and listened to it during (24) I was surprised how at (25) times of the day, the clock would strike three times, six times or more, with a wonderful great (26) that echoed throughout the house. The clock chimed year after year, a part of my (27) , a part of my heart.

Even more (28) to me was my grandfather’s special action each day. He meticulously (29) the clock with a special key each day. The key was magic to me. It (30) our family’ s magnificent clock ticking and striking all year round.

25（）

A. busy

B. urgent

C. happy

D. different
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