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问题 填空题

制作底面半径为2m，高为6m的圆柱形油罐（有两底，不计接缝）需铁皮______m2（用含有π的代数式表示）．

答案

它的侧面积为2π×2×6=24πcm2．

底面积为π×22=4πcm2．

所以需要铁皮面积为24π+2×4π=32πm2．

故答案为：32π．

完形填空

SECTION C

Directions: Complete the following passage by filling in each blank with one word that best fits the context.

Baby survives after train hits pram

The CCTV footage (片段）shows a baby’s pram (婴儿车)rolling off a train platform as the mother makes a mad rush to save her son,   48   she is too late and it falls   49   the rails in front of an incoming train. This heart-stopping scene happened yesterday at Ashburton station in Melbourne, Australia. But the story has a   50   ending: the six-month-old baby survived with just   51   cut on his forehead, although the pram was dragged about 35 meters by the braking train. The nurse Jon Wright said the boy just “needed a feed and a sleep”.

“Luckily, he was strapped (绑) into his pram at the time, which probably saved   52  life. I think the child is extremely   53  ,” Wright told the Herald Sun newspaper after the baby was taken to hospital with minor injuries. The footage shows the mother taking her hands off the three-wheeled pram, which begins to roll   54 the platform edge. 

The driver put on the brakes   55   he saw the pram fall in front of him and fortunately the train was already slowing down to stop at the station. Rail firm Connex is to look into how the pram rolled off the platform. The accident came one day after Connex started a child safety awareness campaign warning parents to keep babies strapped into their prams at all times while on platforms.
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单项选择题

下列选项中，关于不发火面层中粗骨料的试验，说法错误的是（）

A.从不少于50个试件中选出做不发生火花试验的试件10个

B.被选出的试件，应是不同表面、不同颜色、不同结晶体、不同硬度的

C.每个试件重50～200g，准确度达到1g

D.试验时也应在完全黑暗的房间内进行
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