首页
财务会计
医药卫生
金融经济
考公考编
外语考试
学历提升
职称考试
建筑工程
IT考试
其他
登录
学历提升
space is a dangerous place , not only because of meteors but also because of ...
space is a dangerous place , not only because of meteors but also because of ...
admin
2020-12-24
13
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 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 crew accumulated a large amount of rems.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.
46.It can be inferred from the passage that( ).
选项
A.the Apollo mission was very successful
B.protection from space radiation is no easy job
C.astronauts will have deformed children or grandchildren
D.radiation is not a threat to well-protected space explorers
答案
B
解析
由最后一句 “Drugs might... but no really effective ones have been found so far.”可知,目前人类还没有找到有效的方法去避免辐射的危害,所以免受辐射危害并非易事,故选B。
转载请注明原文地址:https://ti.zuoweng.com/ti/GFVCKKKQ
相关试题推荐
spaceisadangerousplace,notonlybecauseofmeteorsbutalsobecauseof...
spaceisadangerousplace,notonlybecauseofmeteorsbutalsobecauseof...
spaceisadangerousplace,notonlybecauseofmeteorsbutalsobecauseof...
spaceisadangerousplace,notonlybecauseofmeteorsbutalsobecauseof...
随机试题
肿瘤化疗的主要副反应是 A.口腔溃疡 B.胃肠道反应 C.骨髓抑制 D.
通过创设良好的情境,潜移默化地培养学生品德的德育方法是()。
蛋白质合成后经化学修饰的氨基酸是( )。
根据《建筑法》,建筑工程安全生产管理应建立健全()制度。
依据《中华人民共和国土地管理法》,应经由国务院批准方可征用的土地有()。
下列哪项不是硫磺的功能 A.杀虫B.壮阳 C.通便D.止痒
讲话稿: 某大学某学院2018级大学新生军训讲话稿
()对有效的风险管理承担最终责任。A、监事会B、董事会C、合规管理部门D、督察长
左旋多巴抗帕金森病的作用机制是A:在外周脱羧转变成DA起作用B:促进中枢DA能神经元释放DA起作用C:进入脑内脱羧生成DA起作用D:直接激动中枢神经系统D
对于经营多年、历史统计数据和资料较多的商品,最适合采用的定量预测方法是()。A:德尔菲法B:类推法C:.用户调查法D:移动平均数法