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
Many people believe the glare from snow causes snow blindness. Yet, dark glasses or not they find themselves suffering from head
Many people believe the glare from snow causes snow blindness. Yet, dark glasses or not they find themselves suffering from head
admin
2015-01-09
42
问题
Many people believe the glare from snow causes snow blindness. Yet, dark glasses or not they find themselves suffering from headaches and watering eyes, and even snowblindness, when exposed to several hours of "snow light".
The United States Army has now determined that the glare from snow does not cause snow-blindness in troops in a snow-covered country. Rather, a man’s eyes frequently find nothing to focus on in a broad expanse of a snow-covered area. So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at. Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscle aches. Nature balances this annoyance by producing more and more liquid which covers the eyeballs. The liquid covers the eyeballs in increasing quantity until vision blurs . And the result is total, even though temporary, snowblindness.
Experiments led the Army to a simple method of overcoming this problem. Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape. Even the scouts themselves throw lightweight, dark-colored objects ahead on which they too can focus. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop searching through the snow-blanketed landscape. By focusing their attention on one object at a time, the man can cross the snow without becoming hopelessly snowblind or lost. In this way the problem of crossing a solid white area is overcome.
Snow-blindness may be avoided by_____.
选项
A、concentration on the solid white area
B、providing the eyes with something to focus on
C、searching for something to look at in snow-covered areas
D、covering the eyeballs with liquid
答案
B
解析
从第三段最后两句可知B为正确答案。
转载请注明原文地址:https://jikaoti.com/ti/406YFFFM
0
考博英语
相关试题推荐
OnJanuary11th,aremarkablelegalcaseopensinaSanFranciscocourtroom—onitsway,itseemsalmostcertain,totheSupreme
Negotiationisnotlimitedtothecorporateboardroomortohigh-stakesbusinesssettings.Bybecomingfamiliarwithsimplenego
ThefamiliarsoundsofanearlyEnglishsummerarewithusonceagain.MillionsofchildrensitdowntoSATs,GCSEs,AS-levels,
Havingafewtoomanydrinkscanmeanmorethanjustablackoutorabadhangover.Peoplewhoengageinbingedrinkingarecourt
Aconsiderableamountofmedicalresearchisaimedatidentifyingriskfactorsfordisease.Therationalebehindthisworkisth
One’sthoughtsmustbedirectedtothefuture,andAtothingsaboutwhichthereissomethingtobedone.Thisisnotalwayseasy
Therearethreeseparatesourcesofhazard【1】totheuseofnuclearreactiontosupplyuswithenergy.Firstly,theradioactivem
AnOhioStateUniversitystudyhaslinkedbehaviorinyoungchildren【1】thetypeofjobtheirmotherhas.Motherswithcomplexoc
Cultureisactivityofthought,andreceptivenesstobeautyandhumanefeeling.【1】ofinformationhavenothingtodowithit.Am
Allenwillsoonfindoutthatreallifeisseldomassimpleasitis______incommercials.(2006年中南大学考博试题)
随机试题
弥散性血管内凝血的临床表现中最常见的早期症状是()
A《纽伦堡法典》B《赫尔辛基宣言》C《希波克拉底誓言》D《大医精诚》E《伤寒杂病论》西文最早的经典医德文献是
[2006年,第22题]当下列哪项成立时,事件A与B为对立事件()。
在项目国民经济评价中,下列关于影子工资及影子工资换算系数的表述,正确的有()。
无机结合料稳定类的石灰工业废渣稳定土,可分为石灰粉煤灰类与石灰其他废渣两大类,除粉煤灰外,可利用的工业废渣包括( )。
定义的使命是抽象、概括出某类事物的本质特征。当定义概括不了时,本应修正定义,而有人却常常“开除”那些概括不了的同类事物,以维护定义的纯洁性,这无疑是__________。填入画横线部分最恰当的一项是()。
假设某公司计划购置一个铜矿,需要投资600000元。该公司购置铜矿以后,需要购置运输设备将矿石运送到冶炼厂。公司在购置运输设备时有两种方案:投资方案甲是投资400000元购买卡车,而投资方案乙是投资4400000元安装一条矿石运送线。如果该公司采用
下面程序的输出结果是【】。#include<iostream.h>voidmain(){inta[6]={1,2,3,4,5,6};for(inti=0;i<5;i++)
Scientificresearchresultscannowbequickly_____tofactoryproduction.
Themostnoticeabletrendamongtoday’smediacompaniesisverticalintegration--anattempttocontrolseveralrelatedaspects
最新回复
(
0
)