法国化学家_1在前人工作的基础上，通过实验得出了空气是由_2组成的结论。空气中各成分的体积分数，大致是_378%，_421%，_50.94%，_60.03%，其它气体和杂质的体积分数是_7。

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法国化学家 ____在前人工作的基础上，通过实验得出了空气是由 ____组成的结论。空气中各成分的体积分数，大致是 ____78%， ____21%， ____0.94%， ____0.03%，其它气体和杂质的体积分数是 ____。

上一题下一题 0.0难度选择题更新时间:2018-01-11 04:53:52

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拉瓦锡,氧气和氮气,氮气,氧气,稀有气体,二氧化碳,0.03%

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Look at this photo. The girl is from Beijing. She is six years old. She is not tall and she has short black hair. She has big eyes, a small nose and a wide mouth. She is in old clothes. Now she is lost（丢失了）. Please help us find her. Our phone number is （010）8699-8886. Thanks!
阅读短文，完成下列表格关于the girl的信息，每个空格一词。

From	____	Looks
Age	Six	She is ____ and she has short ____ hair. Her eyes years are big. She has a ____ nose and a ____mouth.
Tel	（010）8699-8886

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