题干

古代人有在元宵节燃放孔明灯(如图)祈福的风俗.孔明灯燃气的火焰温度可达300℃,但纸质(着火点约170℃)灯罩却没被点燃的原因是(  )

A:灯罩的材料不是可燃物

B:灯罩没有与氧气充分接触

C:风将热量吹散使纸质灯罩处温度低于纸的着火点

D:风将热量吹散后纸质灯罩的着火点降低了

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C

同类题5

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Tom and Steve were twin brothers. Tom loved to play basketball. But Steve loved to read books. One day Tom was playing basketball    21  he fell and broke his leg. When they took him to the hospital, the doctor said he wouldn’t be able to play for six months. Steve went    22  him to and brought him books on basketball. At first Tom wasn’t going to read them. Then he began to read them and 23 that there were ways he could play basketball better. He began to think that books weren’t    24  .

    When Tom’s leg started getting better, Steve would help him by going for walks with him.  25 Tom’s doctor said he could start playing basketball again. Then Tom showed Steve how to toss(投)for baskets. Steve found that he enjoyed it.

    Then Tom was ready to   26   the basketball games. Steve went to watch the games and enjoyed himself. They then    27   practiced basketball and read books together.

    So you can see, when    28    happens, something good may also happen. Steve showed Tom about books and Tom showed Steve about basketball.

So you can also   29   showing others something that you like to do and they can show you something that they like to do. 30 you can find new things to do.

21A. until              B. when            C. after           D. where

22A. on seeing          B. to call            C. to visit         D.to look

23A. saw              B. looked            C. read           D. found

24A. good             B. bad              C. better           D. worse

25A. But              B. However          C. Finally         D. So

26A. take              B. win              C. lose            D. join in

27A. always            B. never            C. seldom          D. much

28A. anything good      B. something nice     C. something bad   D. anything wrong

29A. try               B. practice           C. enjoy          D. like

30A . On the way       B. By the way        C. In a way       D. In this way