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
专升本
Space is a dangerous place, not only because of meteors but also because of rays from the sun and other stars. The atmosphere ag
Space is a dangerous place, not only because of meteors but also because of rays from the sun and other stars. The atmosphere ag
admin
2011-07-31
40
问题
Space is a dangerous place, not only because of meteors 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 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 ream 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 crew accumulated a large amount of reams. So far, no dangerous amounts of radiation have been reported, but 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 a space laboratory. Drugs might help to decrease the damage done by radiation, but no really effective ones have been found so far.
We know from the passage that ______.
选项
A、exposure to even tiny amounts of radiation is fatal
B、the effect of exposure to radiation is slow in coming
C、radiation is avoidable in space exploration
D、astronauts in spacesuits needn’t worry about radiation damage
答案
B
解析
转载请注明原文地址:https://kaotiyun.com/show/DklC777K
本试题收录于:
英语题库成考专升本分类
0
英语
成考专升本
相关试题推荐
FandiwonthePlayer-of-the-Matchawardbecausehewasthemost______playerinthematch.
(Regardlessofyourage),youcanmakeanumberofimportantchangesinyourcurrentlifestylethatcanhelpyoutobecomeheal
Whatisthepassagemainlyabout?U.S.marketersareabletoofferafairlylowpricebecause
Butinrecentyearsithasbecomemoreandmoreevidentthatthispursuithasledtoa"bravenewworld"ofconsumergoodsands
Theauthorthoughtofhisfiend’squestionasagoodone,because______.Fromthepassage,wecanlearnthattheauthor’satti
Accordingtothefirstparagraph,theatmosphereisessentialtomaninthat______.Thebesttitleforthispassagewouldbe_
Accordingtothefirstparagraph,theatmosphereisessentialtomaninthat______.Itcanbeinferredfromthepassagethat_
Children,especially,lovefastfoodbecauseit’sfingerfood,nostrugglingwithknivesandforks,noannoyinginstructionsfro
HowmanyoftheAmericansarelefthanders?Amongtheleft-handers______.
ImagineyouareAlice,steppingthroughthelookingglass.Suddenlyeverythingisreversed.Doorknobsareonthewrongsideof
随机试题
选项的图片中,含量测定指标成分属于异喹啉类生物碱的中药是
下列除哪项外,均可导致气管向健侧移位
4岁患儿,女。因全身浮肿,以肾病综合征收入院。体检:面部、腹壁及双下肢浮肿明显。化验检查:尿蛋白(++++),胆固醇升高,血浆白蛋白降低。
香港甲公司与内地乙公司订立供货合同,约定由香港法院管辖。后双方因是否解除该合同及赔偿问题诉诸香港法院,法院判乙公司败诉。依相关规定。下列哪一选项是正确的?(2009年试卷一第39题)
新征用耕地应缴纳的城镇土地使用税,其纳税义务发生时间是()。
期权交易是一种协议,它给协议一方拥有在一定时期内以一定的价格买进或卖出某种资产的权利,协议的另一方则承担在约定时期内卖出或买进这种资产的义务,期权的两个基本要素是()。
借助思维,人可以把形状、大小各不相同而能结出枣子的树木归一类,称之为“枣树”;把枣树、杨树、银杏、按树等依据其有根、木质茎、叶等共I生归在一起,称之为“树”。这体现了思维的()。
在化学教学过程中,教师有目的地引入或创设具有一定情绪色彩的生动具体的场景,以引起学生一定的态度体验,从而帮助学生理解教材,并使学生的心理机能得到发展的教学方法是()。
Somedoctorsaretakinganunusualnewapproachtocommunicatebetterwithpatients—theyareletting【C1】________readthenotest
U.S.ratesofdiseaseandsomecancers,【B1】______ofthebreast,areamongthehighestintheworld.Manyfactors【B2】______tocan
最新回复
(
0
)