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
2010-02-17
53
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、can raise the temperature of Mars
B、can protect living beings from harmful rays
C、can change the atmosphere of Mars
D、is an important part of the air people breathe
答案
D
解析
转载请注明原文地址:https://kaotiyun.com/show/MynK777K
0
专业英语四级
相关试题推荐
Belowaretwoexcerptsonanimportantconcernofmusicindustry:whetheritiscorrecttosharemusicwithoutpayingornot.
PassageFour(1)Thegenderpaygapforfull-timeworkershasfallenbelow10%forthefirsttimein15yearssincecompara
PassageFour(1)Thegenderpaygapforfull-timeworkershasfallenbelow10%forthefirsttimein15yearssincecompara
PassaqeThree(1)Oneoftheparadoxesofhumanbiologyisthattherichworldhasfewerchildrenthanthepoorworld.Inm
Effortstoeducatepeopleabouttherisksofsubstanceabuseseemtodetersomepeoplefromusingdangeroussubstances,ifsuch
Hewas______herinintelligence.
Thepatient’sprogresswasveryencouragingashecould_____getoutofbedwithouthelp.
Thewaythatpeoplespendtheirmoney,andtheobjectsonwhichtheyspendit,arethelastareaswherefreechoiceandindi
Lungcancerhasnow______breastcancerasacauseofdeathforwomenintheU.S.
WhichVitaminBoostsBrainPower?VitaminEhasbeentoutedforitsanti-agingandanti-cancerbenefitsbecause,asananti
随机试题
屈光参差性弱视的叙述不正确的是()
下列哪项心电图改变不是急性心包炎的常见
下列哪种流产易诱发感染
元朝为了保证对汉人的严格控制,在官僚管理体制方面广泛地进行行政管理规范立法,尤其是制定了大量的监察法规,以下属于行政监察性法规的是()。
关于模板搭设、拆除要求,正确的有()。
股权投资基金投资后管理的增值服务不包括()。
我国和______、______是世界三个著名的玉器工艺品产地。
()的目的是提高社区成员及社区团体对社区的认同,鼓励他们通过自助和互助解决社区问题。
=_______.
Whoisresponsibleforthemanagementofschools?
最新回复
(
0
)