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
2016-08-29
56
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。
转载请注明原文地址:https://kaotiyun.com/show/6pG7777K
0
大学英语六级
相关试题推荐
A、Therearenotenoughefficientmanagers.B、Itlacksinguidelinesfornewemployees.C、Theconferencescheduleshouldchangei
A、Therewillbelotsofjobopportunitiesinthesetwoareas.B、Therewillbelessjobopportunitiesinthesetwoareas.C、There
Thewaypeopleholdtothebeliefthatafun-filled,painfreelifeequalshappinessactuallyreducestheirchancesofever【B1】
A、Requiredtextbooks.B、Usedbooks.C、Booksona"suggestedreadings"list.D、Children’sbooks.A
A、ThefreezingweatherinBrazil.B、Theimpactofglobalwarming.C、Theincreasedcoffeeconsumption.D、Thefluctuationofcoffe
Lastyear,Iwroteapieceentitled"WhywewronglyfreakoutoverAP?"ThreetofiveAdvancedPlacementcoursesinhighschool
Lawyerswhoofferfreelegalhelpfortheirclientsarecommonlycalled"probono"lawyers.Inrecentyears,therehasbeen【B1】_
A、Themanshouldchecktheweatherreportinthepaper.B、Thepaperwillbedeliveredthisafternoon.C、Therainwillnotlasta
Dohalfofallmarriagesreallyendindivorce?It’sprobablythemostoften【B1】_____statisticaboutmodernlove.Butinanupbe
孙大圣是中国古典文学名著《西游记》(JourneytotheWest)中的一个重要人物。他是唐僧(TangMonk)第一个徒弟。其实在中国,他最受欢迎的名字不是“孙大圣”,而是“孙悟空”,这是教他72变(the72supernormalabi
随机试题
行政管理机构作为一种对社会公共事务管理的机构,基于以上特性,主要具有以下两方面的作用:
下列脾破裂的处理错误的是
(2016年真题)秦律规定;“盗封啬夫可(何)论?廷行事以伪写印。”这里的“廷行事”是指()。
关于生活垃圾填埋场渗滤液处理的说法,正确的有()。
政府机构构成的六要素中,属于政府机构行使行政权力、履行行政职责的物质基础是()。
1,4,13,40,121,()
图的广度优先周游类似于树的()。
关于ARM处理器的命名,以下说法错误的是()。
【B1】______TheDailyMirrorandtheDailyExpressbothsellaboutfourmillioncopieseveryday.Apartfromthenationalpapers,
TheClassicalSenseofGoodGovernmentPoliticsplaysanextremelyimportantroleinhumansociety.Politicalphilosophersst
最新回复
(
0
)