列物质按质量由大到小的顺序排列正确的是( ) ①2个铝原子 ② 1×10-2mo

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问题:

列物质按质量由大到小的顺序排列正确的是      (    )

①2个铝原子   ② 1×10-2mol铜  ③6个水分子  ④ 0.5g二氧化碳

⑤ 1×10-3mol臭氧(O3

A ④>②>⑤  B②>①>③   C  ⑤>③>①  D ④>③>②

考点:物质的量
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设命题甲:ax2+2ax+1>0的解集是实数集R;命题乙:0<a<1,则命题甲是命题乙成立的(  )

A.充分非必要条件

B.必要非充分条件

C.充要条件

D.既非充分又非必要条件

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卸车定额损耗量的计算公式是:卸车定额损耗量=卸货前罐车计量数/卸车定额损耗率

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It’s difficult for doctors to help a person with a hurt brain.  36  enough blood, the brain can live only three to five minutes. Usually doctors can’t fix the hurt  37  such a short time.
Dr Robert White thinks he knows a  38  of help. He thinks doctors should make the hurt brain  39  to live for 30 minutes without blood. This gives the doctor  40  time to do something for the brain. Dr White experimented his  41  on fifteen monkeys.  42  he taught them to do different jobs. Then he operated on them. He made the monkeys’ blood go  43  a machine. When the brains’  44  was 10℃, he stopped the blood to the brain. After 30 minutes, he turned the blood back on. He  45  the blood again. After their operations, the monkeys were almost  46  before. They were healthy and busy. Each one could still do the job the doctor  47  them.
Dr White’s idea works well on monkeys. He thinks it will work on  48 . He think it will help with heart problems. A person  49  die when his heart stops; doctors can  50  it again. The problem comes: when the brain is without blood for about 5 minutes, it  51 . If doctors start the heart again after 5 minutes, the person has  52  body but a dead brain. Maybe in the future, doctors will  53  Dr White’s idea. When the person’s heart stops the doctor will  54  cool the brain. They will have 30 minutes to start the heart again. Maybe there will be no  55  the brain.
小题1:
A.Don’t haveB.WithoutC.Having notD.Only with
小题2:
A.forB.afterC.inD.since
小题3:
A.wayB.brainC.doctorD.man
小题4:
A.too coolB.enough coolC.cool enoughD.that cool
小题5:
A.a longerB.enoughC.a shorterD.another
小题6:
A.medicineB.mannersC.ideaD.brain
小题7:
A.BesidesB.InsteadC.HoweverD.First
小题8:
A.to B.acrossC.throughD.onto
小题9:
A.heatB.temperatureC.coolnessD.feeling
小题10:
A.cooledB.operatedC.warmedD.stopped
小题11:
A.the same asB.different fromC.used toD.cleverer than
小题12:
A.was taughtB.was teachingC.was to teachD.had taught
小题13:
A.other peopleB.human beingsC.other thingsD.more people
小题14:
A.doesn’t have toB.needn’tC.will be able toD.is afraid to
小题15:
A.startB.takeC.makeD.begin
小题16:
A.losesB.goesC.killsD.dies
小题17:
A.noB.a deadC.a livingD.a lively
小题18:
A.get B.acceptC.keepD.try
小题19:
A.soon B.quickly C.slowlyD.rapid
小题20:
A.use forB.wrong withC.value toD.problem with
题型:选择题

1654年,德国学者奥托•格里克表演了一个惊人的实验,有力地证明了大气压强的存在,后来把这个实验叫做______.十七世纪四十年代,意大利的科学家______首先测出了大气压的值.

题型:选择题

林木修枝

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