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、When the sun is very active and explosions occur. B、When it is less than 1,500 miles away from the earth. C、When bad weather o
A、When the sun is very active and explosions occur. B、When it is less than 1,500 miles away from the earth. C、When bad weather o
admin
2023-02-20
17
问题
Not long ago it was assumed that the dangers man would meet in space would be terrible, the main ones being radiation and the danger of being hit by meteors. It is perhaps worth remembering that less than two centuries ago the dangers of train travel seemed similarly terrible. A man would certainly die, it was thought, if carried along at a speed of thirty kilometers per hour.
There are two sorts of radiation man must fear in space. The first is radiation from the sun, and this is particularly dangerous when the sun is very active and explosions are occurring on its surface. The second, less harmful form comes from the so-called Van Allen Belts. These are two areas of radiation about 1,500 miles away from the earth. Neither of these forms of radiation is a danger to us on the earth, since we are protected by our atmosphere. Specifically, it is that part of our atmosphere known as the ozonosphere which protects us. This is a belt of the chemical ozone between 12 and 21 miles from the ground, which absorbs all the radiation.
Once outside the atmosphere, however, man is no longer protected, and radiation can be harmful in a number of ways. A distinction must be drawn between the short- and long-term effects of radiation. The former are merely unpleasant, but just because an astronaut returning from a journey in space does not seem to have been greatly harmed, we cannot assume that he is safe. The long-term effects can be extremely serious, even leading to death.
9. What was one of the main dangers man would meet in space?
10. When is the sun radiation particularly dangerous to human beings?
11. Why did the speaker say neither of these forms of radiation is a danger to us?
选项
A、When the sun is very active and explosions occur.
B、When it is less than 1,500 miles away from the earth.
C、When bad weather occurs more frequently.
D、When there is less forest on the earth.
答案
A
解析
原文提及“太阳的辐射在太阳活跃时或在太阳表面有爆炸发生时尤其危险”。故A正确。事实细节题。原文提到一个叫Van Allen Belts的辐射区域,它们距离地球不到1500英里,这跟太阳的辐射没有关系,B错误;C和D未提及。
转载请注明原文地址:https://kaotiyun.com/show/mrvD777K
0
大学英语六级
相关试题推荐
TheexactnumberofEnglishwordsisnotknown.Thelargedictionarieshaveoverhalfamillionentries,butmanyofthesearec
W:Doyouknowthegirlinredunderthetree?M:【D1】________W:Right.Doyouknowher?M:Ofcourse.She’sLily.【D2】________W
JaimeJavierRodrigueznotesthatpopularartformsoftenconcealadauntingcomplexity:frequentlywhatappears________becomes
农业要保持粮食供应。从供给数量看,2019年我国粮食产量再创新高,棉油糖生产稳定,果菜茶供应充足,但是公众关注生猪供给。受非洲猪瘟等因素影响,今年生猪产能下降较多。一场生猪稳产供保行动在全国各地展开,政府部门从财政支持、用地保障、金融保险等方面持续发力。目
Whentheattackbegan,theloudnoiseofexplosionsmadepeoplescurrytoseekcover.
Thecompanysponsorsanessaycompetitionthatstudentssubmitpapers,apanelofhistorianswilljudgethemonthebasisofsty
把亲情放在适当的位置上双方都不致失落。人到中年.亲情的互动,是阶段性的幸福,不要赋予它太严肃的意义,也不要把它看得无足轻重。孩子不应永远记住父母入骨的爱,那将使他们无法成长:父母也不应永远记住自己对儿女所作的牺牲,那将使老人陷于期待回报的自怜。而且,事实上
人类文明迄今已经历了原始文明、农业文明和工业文明,目前,人类社会正处在由工业文明向生态文明的转型期。工业文明是以经济快速发展、社会财富不断快速增长为标志.极大地满足人们对物质的需求。由于工业文明的快速发展。中国已成为世界制造业大国,随之而来的是资源的过度开
C细节辨认题。当男士问女士NEA基金会是一个什么样的机构,为教师提供哪些支持时,女士提到该基金会致力于为学生改善公共教育、每年向教育工作者发放三次补助金、每年颁发优秀教学奖等,由此判定选项A、B、D均与原文不符。C项与原文中的“Educatorscan
(1)Teachersbelievethattoughexamsarediscouragingpupilsfromlearninglanguages,accordingtoanewBritishCouncilsurvey
随机试题
A.肝阳化风B.热极生风C.阴虚风动D.血虚生风(2008年第83,84题)症见肢麻不仁、甚则丁,其病机是()
焊缝及熔敷金属拉伸试样的直径为6mm时,其尺寸极限偏差为()。
根据《中华人民共和国环境影响评价法》,建设项目的环境影响评价文件自批准之日起超过五年,方决定该项目开工建设的,其环境影响评价文件应当报原审批部门()。
居住区内住宅层数的平均值指()。
1.背景某项目经理部负责本地网直埋光缆线路环网工程的施工,合同规定采用包工不包料的形式承包,工程的路由报建工作已由建设单位完成,工程于4月15日开工,工期37天。该工程包括三个中继段,其中A中继段为50km、B中继段为60km、C中继段为70km
奈普科技公司系江海市大型股份制企业。市税务局稽查局对奈普科技公司的纳税情况依法实施检查,发现奈普科技公司2017年6月至12月存在未按规定申报纳税的情况。市税务局稽查局根据税收法律、法规和有关规定,作出《税务处理决定书》,责令奈普科技公司补缴税款3260.
Communicationstechnologiesarefarfromequalwhenitcomestoconveyingthetruth.Thefirststudytocomparehonestyacrossa
在数据库中,产生数据不一致的根本原因是
OurEnglishteacherinsistedthatwespendmoretimeon______reading.
Todaywetalkaboutthedifferencebetweenacollegeandauniversity.Collegesanduniversitieshavealotin【B1】______.Theyp
最新回复
(
0
)