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
Space is a dangerous place, not only because of meteors (流星), but also because of rays from the sun and other stars. The atmosph
Space is a dangerous place, not only because of meteors (流星), but also because of rays from the sun and other stars. The atmosph
admin
2011-02-28
44
问题
Space is a dangerous place, not only because of meteors (流星), but also because of rays from the sun and other stars. The atmosphere again acts as our protective blanket on earth. Light gets through, and this is essential, for plants to make the food which we eat. Heat, too, makes our environment endurable. Various kinds of rays come through the air from outer space, but enormous quantities of radiation (辐射) from the sun are screened off. As soon as men leave the atmosphere they are exposed to this radiation but their spacesuits or the walls of their spacecraft, if they are inside, do prevent a lot of radiation damage.
Radiation is the greatest known danger to explorers in space. The unit of radiation is called "rem". Scientists have reason to think that a man can put up with far more radiation than 0.1 rem without being damaged; the figure of 60 rems has been agreed on. The trouble is that it is extremely difficult to be sure about radiation damage — a person may feel perfectly well, but the cells of his or her sex organs may be damaged, and this will not be discovered until the birth of deformed (畸形的) children or even grandchildren. Missions of the Apollo flights have had to cross belts of high radiation and, during the outward and return journeys, the Apollo missions have been quite short. We simply do not know yet how men are going to get on when they spend weeks and months outside the protection of the atmosphere, working in space laboratory. Rugs might help to decrease the damage done by radiation, but no really effective ones have been found so far.
The harm radiation has done to the Apollo crew members ______.
选项
A、is insignificant
B、seems overestimated
C、is enormous
D、remains unknown
答案
D
解析
依据是:So far,no dangerous amounts of radiation have been reported,but Apollo missions have been quite short.C文中未提及,A和B与文章事实不符。
转载请注明原文地址:https://kaotiyun.com/show/yVtd777K
本试题收录于:
公共英语三级笔试题库公共英语(PETS)分类
0
公共英语三级笔试
公共英语(PETS)
相关试题推荐
Sincethedawnofhumaningenuity,peoplehavedevisedevermorecunningtoolstocopewithworkthatisdangerous,boring,burd
Beingamanhasalwaysbeendangerous.Thereareabout105malesbornforevery100females,butthisratiodropstonearbalanc
Beingamanhasalwaysbeendangerous.Thereareabout105malesbornforevery100females,butthisratiodropstonearbalan
Sincethedawnofhumaningenuity,peoplehavedevisedevermorecunningtoolstocopewithworkthatisdangerous,boring,burd
Sincethedawnofhumaningenuity,peoplehavedevisedevermorecunningtoolstocopewithworkthatisdangerous,boring,burd
Therateofpopulationgrowthisfastestinunderdevelopedcountries.Inthesecountriesahighbirthrateisaccompaniedbyal
Thewritersuggeststhatpolicymakersshouldconsiderculturalvalues______.Alargepopulationinanunderdevelopedcountry
Whatisthesubjectofthisconversation?
Whatisthesubjectofthisconversation?
随机试题
Borrowingtostartabusinessisnoteasy.Gettingabankloan,particularlyforanewsmallbusiness,islikegoingthroughthe
袋底位于牙槽嵴冠方的牙周袋称为假性牙周袋又称为
某住宅项目的施工单位为了能够春节前完成结构封顶,未经监理人员同意擅自浇捣顶层混凝土楼板。监理工程师发现后,要求施工单位采取措施确保工程质量。但最终由于该批混凝土存在严重质量问题,已经对工程的安全功能构成威胁,必须拆除后重新施工。经估算,直接经济损失将达到6
试述压电式加速度计是如何工作的。
依次填入列各句横线处的词语,最恰当的一组是()。 ①随着社会的发展,________教育越来越引起人们的关注。②分别二十多年后,同学们再相聚时,我已经很难________出小学时的同桌了。③这里出产的绿茶久负盛名,要仔细_
下列哪些行为构成非国家工作人员受贿罪?()
[2001年MBA真题](1)一(2)基于以下题干:以下是某市体委对该市业余体育运动爱好者一项调查中的若干结论:所有的桥牌爱好者都爱好围棋;有围棋爱好者爱好武术;所有的武术爱好者都不爱好健身操;有桥牌爱好者同时爱好健身操。如果上述结论都是真实的,则以下
综合布线工程实施过程中,监理工程师应当按照(16)审查承建单位人员施工是否符合要求。
WhatIsaDream?Forcenturies,peoplehavewonderedaboutthestrangethingsthattheydreamabout.Somepsychologistssay
ThePresidentduringtheAmericanCivilWarwas
最新回复
(
0
)