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
2024-06-18
3
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
What is one of the things that must be done before man can live on Mars?
转载请注明原文地址:https://tihaiku.com/zcyy/3638937.html
相关试题推荐
[originaltext]Sciencefictionwritershaveoftenimaginedhumanbeingsgoin
[originaltext]Sciencefictionwritershaveoftenimaginedhumanbeingsgoin
[originaltext]Sciencefictionwritershaveoftenimaginedhumanbeingsgoin
[originaltext]Sciencefictionwritershaveoftenimaginedhumanbeingsgoin
[originaltext]Today,airtravelisfarsaferthandrivingacaronabusym
[originaltext]WehavetendedtoviewYogaasakindofforeignreligiousex
[originaltext]WehavetendedtoviewYogaasakindofforeignreligiousex
[originaltext]M:Hello.InternationalFriendsClub.CanIhelpyou?W:Oh,hell
[originaltext]M:Hello.InternationalFriendsClub.CanIhelpyou?W:Oh,hell
[originaltext]M:So,Rebecca,whatdidyoudoforspringbreak?W:Iwenttoso
随机试题
Peoplewhoaretoohappydieyoungerthantheirmoredownbeatpeers,claims
Businessesarestructuredindifferentwaystomeetdifferentneeds.The【B1】
下列设计措施中,哪一条对于控制建筑物体型系数是不利的?()A.平面空间尽量减
培训总结是在培训评估的基础上,对培训全过程的科学合理地报告。
下列有关自来水厂投加液氯消毒的表述中,哪几项不正确?()A.相对来说,水的浊
典型调查的结果通常可用以推算调查总体数值。( )
患者,女性,30岁,反复发作性喘息3年,近1年来发作频繁,重时端坐呼吸。查体:心
()是指因宏观政策的变化导致的对基金收益的影响。A、政策风险 B、经济周期性
()是企业,特别是大中型企业实施高度集中管理的科技开发组织,在本企业(行业)
下列关于建筑工程一切险的保险期限描述错误的是()。A.保险期限不得延长
最新回复
(
0
)