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
A、Because people might have to migrate there someday. B、Because it is very much like the earth. C、Because it is easier to explor
A、Because people might have to migrate there someday. B、Because it is very much like the earth. C、Because it is easier to explor
admin
2013-06-02
36
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 were like that of Earth, this might be possible. But m fact, it s mostly carbon dioxide(CO2). Apart from that, there are other problems to be overcome. For example, the temperature would have to be raised from 60~C below zero to 15~C 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 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’re 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 100,000years.
选项
A、Because people might have to migrate there someday.
B、Because it is very much like the earth.
C、Because it is easier to explore than other planets.
D、Because its atmosphere is different from that of the earth.
答案
A
解析
语意理解题。解答本题的关键是overcrowding(人门过多),探索火星或许可以解决地球上人口过多的问题,即意味着或许有一天人们可以向火星移民,因此选项A正确。
转载请注明原文地址:https://jikaoti.com/ti/Bu5FFFFM
0
大学英语六级
相关试题推荐
A、Themanshouldstartrunningdaily.B、Shealsopreferstoexerciseintheafternoon.C、It’simportanttowarmupbeforeexerci
A、Shewentsailingwiththeman.B、Shewaitedlongtogetasignature.C、Sheappliedforanew-openlesson.D、Shelearnedinal
A、Oilwellsowners.B、Bankers.C、Railroadshareholders.D、Sportsstars.D选项都和职业身份有关。从amillionaireissomeonewhoownsahugewe
InatypicaldayofLaineCaspi,shespendsmostofhertime________.Whatcanbeinferredaboutthelifeofworkingmothersi
A、Takecoursesofforeignlanguagesandcultures.B、Gainadeepunderstandingoftheirownculture.C、Participateininternation
Directions:Forthispart,youareallowed30minutestowriteacompositiononthetopicHarmfulnessofFakeCommodities.Yous
A、Todrivethetrainafteritisstartedautomatically.B、Tostartthetrainandtodriveitwhennecessary.C、Totakecareoft
Ifaneconomistwereaskedwhichofthreegroupsborrowmost—peoplewithrisingincomes,stableincomes,ordecliningincomes—he
Forthispart,youareallowed30minutestowriteashortessayentitledIsItNecessaryforaCollegeStudenttoOwnaMobile
随机试题
什么是实际晶粒度?
简述我国目前获得认可的社区教育的主要模式。
何种情况血液必须被废弃
下列关于证据的理论分类的说法中,哪些选项是不正确的?
债券发行者名称,这一要素指明了该债券的债务主体,既明确了债券发行人应履行对债权人偿还本息的义务,也为债权人到期追索本金和利息提供了依据。()
根据关税法德制度的规定,对原产于与我国签订含有关税优惠条款的区域性贸易协定的国家或地区的进口货物,按()征收关税。
我国现代著名教育思想家陶行知认为幼儿教育应解放儿童的()。
2014年,A省固定资产投资呈现“增速趋缓,结构优化,质量提升”良好发展态势。总量保持较快增长,增速有所回落。2014年,全省完成固定资产投资41552.8亿元,比2013年增长15.5%,增速同比回落4.1个百分点。投资总量中,项目投资完成33
串行通信中,若收发双方的动作由同一个时序信号控制,则称为( )串行通信。
【B1】【B17】
最新回复
(
0
)