首页
登录
职称英语
[originaltext] Science fiction writers have often imagined human beings goin
[originaltext] Science fiction writers have often imagined human beings goin
游客
2024-06-03
49
管理
问题
Science fiction writers have often imagined human beings going to live on Mars. But these days, scientists are taking the idea seriously. It has a great deal to recommend it, since it might solve the problem of overcrowding on the earth. But obviously, it would not be worth making the effort unless people could live there naturally. If the atmosphere were like that of the earth, this might be possible. But in fact it is mostly carbon dioxide. Apart from that, there are other problems to be overcome. For example, the temperature Would have to be raised from 60 degrees below zero to 15 degrees above it. Scientists who study Mars have laid down the program that they can follow. To begin with, they will have to find out whether life has ever existed on the planet of Mars in the past. Secondly, they will have to make a reliable map of its surface. And finally, they will have to make a list of the gases. Above all, they will have to discover how much nitrogen it possesses, since nitrogen is four fifths of the air we breathe. They are surprisingly optimistic about raising the temperature on Mars and believe it could be done in two hundred years. It will take a bit longer, though, to transform the atmosphere so that human beings, could live there. Scientists estimate that this will take one hundred thousand years.
选项
A、Its chemical elements must be studied.
B、Its temperature must be lowered.
C、Big spaceships must be built.
D、Its atmosphere must be changed.
答案
D
解析
文中提到了几个火星不适合人类居住的因素,由其中的lf the atmosphere were like that of the earth,this might be possible.But in fact it is mostly carbon dioxide可推知,D“改善大气环境”是人类移居火星之前必须解决的问题之一。
转载请注明原文地址:http://tihaiku.com/zcyy/3617991.html
相关试题推荐
[originaltext]AgoodwaytoseetheUSAisbycar.Americanslovetheiraut
[originaltext]AgoodwaytoseetheUSAisbycar.Americanslovetheiraut
[originaltext]Whathappenswhenamerchantdisplaysaniteminhisstorewi
[originaltext]W:HiTim!Howareyou?M:Fine,thankyou.W:I’dbeenwondering
[originaltext]M:Hey,Christine,rememberhowwewerecomplainingthatwewante
[originaltext]M:Hey,Christine,rememberhowwewerecomplainingthatwewante
[originaltext]M:Hey,Christine,rememberhowwewerecomplainingthatwewante
[originaltext]M:Thefronttireisflat,andtheseatneedstoberaised.W:Wh
[originaltext]M:Thefronttireisflat,andtheseatneedstoberaised.W:Wh
[originaltext]M:Thefronttireisflat,andtheseatneedstoberaised.W:Wh
随机试题
Professor:Firstofall,allowmetointroduceProfessorJohnBrownfromCambrid
Foryears,scientistshavebeenstudyinghowmusicaffectsthebrainandits
依据《建设工程勘察设计管理条例》,编制初步设计文件应满足( )。A.全部设备材
快硬性硅酸盐水泥出厂两个月后仍可使用。()
细胞分型法判断结果是观察( )。A.细胞增殖程度 B.死细胞百分比 C.凝
患者女性,28岁,甲状腺功能亢进病史半年,妊娠3个月后,甲状腺功能亢进症状加重,
对于公诉人向法庭提出的补充侦查延期审理的建议,法院应当如何处理?A:应当同意B
根据2015年版《中国药典》,有小毒的中药是A.罂粟壳 B.麻黄 C.大黄
某企业2×19年度发生与固定资产有关的业务如下:(1)购入不需安装的设备一台,价
某施工合同实施过程中出现了偏差,经过偏差分析后,承包人采用新的高效率的施工方案。
最新回复
(
0
)