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  • 英語(yǔ)翻譯

    英語(yǔ)翻譯
    The early universe contained only the lightest elements,hydrogen and helium.Heavier elements,such as carbon,form only in nuclear reactions in stars and are dispersed when the stars explode.A recently discovered gas cloud contained carbon several billion years ago,when the universe was no more than two billion years old.
      If the statements above are true,which of the following must,on the basis of them,also be true?
      (A)The earliest stars contained only hydrogen.
      (B)Some stars were formed before the universe was two billion years old.
     ?。–)The carbon in the gas cloud later formed part of some stars.
     ?。―)No stars identified to date are as old as the gas cloud.
      (E)The gas cloud also contained hydrogen and helium.
    英語(yǔ)人氣:265 ℃時(shí)間:2020-04-16 18:27:03
    優(yōu)質(zhì)解答
    E
    A錯(cuò),B錯(cuò),C錯(cuò)先有star后有g(shù)as cloud,D 錯(cuò)star is older than gas cloud額,您的答案和標(biāo)準(zhǔn)答案不符。標(biāo)準(zhǔn)答案錯(cuò)那B為什么錯(cuò)了呢?現(xiàn)有宇宙比較愚鈍,能解釋的詳細(xì)點(diǎn)嗎?宇宙20億歲之前就有星球。這個(gè)是對(duì)的。碳是在星球上生成,20億年前有氣云,氣云是星球爆炸產(chǎn)生的 所以這句話是對(duì)的。那B選項(xiàng)說(shuō)他星球在宇宙之前產(chǎn)生,不是對(duì)的嗎?對(duì)額,那就是這道題目有問(wèn)題,E和B都對(duì)嗎?是的 我覺(jué)得如此
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