题干

阅读下列文字,完成后面小题。

    本报华盛顿1月28日专电记者张允文报道:今天上午美国东部标准时间11点38分,“挑战者”号航天飞机升空约1分12秒后突然爆炸,机上七名宇航员全部罹难。这是美国宇航史上最严重的一次事故,是美国进行56次载人宇宙飞行活动中,发生在空间的第一次大灾难。1967年发射阿波罗飞船时,曾经发生过发射台上的爆炸,造成三名宇航员丧生。

    ……

    美国宇航局官员表示,在搜集和彻底研究全部数据之前,他们对造成这一悲剧的原因不作任何推测,不表示任何看法。然而据来自宇航局的消息,宇航局的专家们把注意力集中于航天飞机的两个固体燃料助推器和庞大的主燃料箱上面。据研究了录像带的专家说,问题可能出现在外挂燃料箱上。燃料箱中存放着200万升液态氢和液态氧,用以推动航天飞机进入轨道。爆炸时,外部燃料箱的尾部首先断裂,把两个固体燃料助推火箭猛推到相反方向。有的专家认为,助推器有燃料外泄的迹象。

上一题 下一题 0.0难度 选择题 更新时间:2018-07-23 12:46:22

答案(点此获取答案解析)

同类题1

阅读下面短文,根据其内容,从方框中选择适当的单词填在标有题号的空白处,使语意通顺、完整.(每空一词,切不可重复使用)

moving    direction    fall      hands      where    protect     yourself

against    as        up     possible     easily     them  thing   ground

 What should you do if you are in a crowd(人群)? The first and most important ____   is to make yourself clear where you are and where the exits are. No matter ____  you are, make sure you always know how to get out and to be safe.

 Make yourself know the type of  ____  you are standing on. Wet or uneven(不平坦的)ground can cause you to ____  down in a crowd of moving people.

 If you find ____   in the middle of a moving crowd, you must be careful. Do not walk ____  the moving direction and do not stop or sit down, because you could get trampled (踩踏)  ____ Instead, move in the same ____  of the crowd. Keep your____  up by your chest(胸部)to protect your chest. If you fall down, get up quickly, If you can't get  ____  , ask someone to pull you back up. If you have kids, lift  ____  up.

 If you fall and cannot get up, keep on  ____   in the same direction of the crowd. If that is not  ____   , then cover your head with your arms.

 Try to get away from hard things in a crowd. If you're pushed against them, ____   a result, you may be hurt badly.

 We should learn to ____  ourselves. Stay away from the crowd.

Remember: Whatever you do, safety is first!