首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Scientists are interested in Mars because_______________.
Scientists are interested in Mars because_______________.
admin
2009-01-05
55
问题
Scientists are interested in Mars because_______________.
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’s mostly carbon dioxide. Apart from that, there are other problems to be overcome. For example, the temperature would have to be raised from 60 below zero to 15 above it. Scientists who study Mars have let out the programme that they can follow. To begin with, they will have to find out whether life has ever existed on the planet 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 200 years. It would take a bit longer, though, to transform the atmosphere so that human beings could live there. Scientists estimate that this will take 100,000 years.
选项
A、people might have to migrate there someday
B、people could live there naturally
C、life has ever existed there
D、its atmosphere is quite different
答案
A
解析
转载请注明原文地址:https://kaotiyun.com/show/yMBK777K
0
专业英语四级
相关试题推荐
LearningaboutCognitiveGrammar(CG),anapproachtotheanalysisanddescriptionoflanguagestructure,isnoteasy.One
A、Natureshouldtakeitscourse.B、Peopletakethingsforgranted.C、Humansaredamagingtheearth.D、Animalsshouldstayawayf
NotwomanheldapresidentialcabinetpositionintheUnitedStatesuntil1933,whenFrancesPerkinsbecamesecretaryoflabor.
ForgetexpensiveeducationalDVDsandprivatetutors,thesecrettosmartchildrencouldbesosimpleasgivingbirth【M1】______
Whatpersonalqualitiesaredesirableinateacher?Probablynotwopeoplewoulddrawupapproximatelysimilarlists,butI【M1】_
Whatpersonalqualitiesaredesirableinateacher?Probablynotwopeoplewoulddrawupapproximatelysimilarlists,butI【M1】_
Foryears,nonprofithospitalshaveshiedawayfromquantifyingtheamountofcharitablecaretheyprovidecommunities.Hospit
Tolive,learn,andworksuccessfullyinanincreasing【S1】______complexandinformation-richsociety,studentsmustbeable
Tolive,learn,andworksuccessfullyinanincreasing【S1】______complexandinformation-richsociety,studentsmustbeable
Accordingtoanewsreport,thedivorcerateinChinahasbeenincreasingeversincethestartof21stcentury.Somepeoplesay
随机试题
《证券法》主要修订的内容包括()。Ⅰ.完善了上市公司的监管制度,提高上市公司质量Ⅱ.加强对证券公司监管,防范和化解证券市场风险Ⅲ.加强对投资者特别是中小投资者权益的保护力度,建立证券投资者保护基金制度Ⅳ.对分业经营和管理、现货交
什么是生理依赖性和精神依赖性?哪些药物易产生依赖性?
A.消食化滞,理气和胃B.健脾和胃,消食止泻C.消食导滞,清热祛湿D.消食导滞,攻积泄热E.温阳健脾,和胃消食保和丸的功效是
以下说法正确的是()
一项工程项目实施完成后,很难推倒重来,这体现了工程建设具有()。
下列关于带电体灭火的操作方法正确的是()。
招标结束后,招标人应将( )退还给未中标的投标人。
心理学家们曾做过这样一个实验:在给小小的缝衣针穿线的时候,你越是全神贯注地努力,线越不容易穿入。在科学界,这种现象被称为“目的颤抖”,也叫“穿针心理”,就是目的性越强就越不容易成功。根据上述定义,下列各项没有体现“穿针心理”的是:
1947年,台湾省人民为反抗国民党当局的暴政举行了()。
Givemeyourtelephonenumber______Ineedyourhelp.
最新回复
(
0
)