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 pilot cannot fly a plane by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must us
A pilot cannot fly a plane by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must us
admin
2011-01-13
76
问题
A pilot cannot fly a plane by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300, 000 kilometers in one second. A radar set sends out a short burst of radio waves: Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word "radar," in fact, gets its name from the term "radio detection and ranging." "Ranging" is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms.
The word "it" underlined in Paragraph 1 refers to ______.
选项
A、a radar set
B、a short burst
C、a radion wave
D、light
答案
A
解析
词义题型参见第95题注释,可知“it”在此指前面所提到的“一个雷达装置”;因此A为答案。
转载请注明原文地址:https://www.kaotiyun.com/show/iy5O777K
本试题收录于:
CATTI三级笔译综合能力题库翻译专业资格(CATTI)分类
0
CATTI三级笔译综合能力
翻译专业资格(CATTI)
相关试题推荐
A、Studentsmightnotconsiderthemtobeanimportantpartofculture.B、Theysymbolizetherebellionofyouthinthe1950’s.C、
A、Shedoesn’tthinkthatshelookslikethestudent.B、Manyofherstudentslookalike.C、Sheisn’trelatedtothestudent.D、He
A、TodemonstrateGeorgeWashington’ssurvivalskills.B、Toshowthatsomestoriesaboutfamouspeoplemaybehistoricallyinaccu
A、Judgingpeople’sbehavior.B、Commoncausesofanger.C、Changingpeople’sattitudes.D、Theeffectsofnegativebehavior.AWhat?
Accordingtothepassage,whydidthefirstpeoplewhocametoNorthAmericaleavetheirhomeland?Whatistheauthor’sattitud
OvercomingtheLanguageBarrierThediscoverythatlanguagecanbeabarriertocommunicationisquicklymadebyallwhotra
OvercomingtheLanguageBarrierThediscoverythatlanguagecanbeabarriertocommunicationisquicklymadebyallwhotra
Somepeopleliketotravelwithacompanion.Otherpeopleprefertotravelalone.Whichdoyouprefer?Usespecificreasonsand
随机试题
简述社会主义市场经济理论的主要内容和意义。
7个月婴儿发热、呕吐、水样便,每天7~8次,已3天,于11月15日入院。查体:体温38.5℃,轻度脱水貌,咽部充血,心、肺(-),肠鸣音稍亢进。大便镜检:脂肪球(++)。最可能的诊断是
流感病毒分甲、乙、丙三型的依据是
甲厂经乙厂许可,在某省独占使用乙厂的注册商标。后发现当地的丙厂也使用了该商标。经查,丙厂是经过外省对同一商标享有独占使用权的丁厂的违法许可而使用该商标的。甲厂的下列请求哪一个不能成立?()
某2.5万t/年离子膜法烧碱扩建工程,属停产检修性的技改工程项目。工程项目包括全厂的旧设备拆除、局部旧设备基础拆除、设备基础及钢筋混凝土底板加固、新建设备基础及全厂设备管道安装调试等。某机电安装工程公司通过招投标承建该项目。该项目工期非常紧张,从停产改造到
爆破加工房应设在洞口( )以外的安全地点。
企业摊销无形资产时,可能借记的会计科目有()。
Inflation【2015招商银行】Businessandgovernmentleadersalsoconsidertheinflationratetobeanimportantgeneralindicator.Infla
Myprevioushomehadastandofwoodsbehinditandmanyanimalsinthebackyard.Thatfirstyear,I【C1】______feedingpeanutsto
给定程序MODll.C中函数fun的功能是:计算函数(x,y,z)=(x+y)/(x-y)+(z+y)/(z-y)的值。其中x和y的值不等,z和y的值不等。例如,当X的值为9、y的值为11、Z的值为15时,函数值为-3.50。请改正程序
最新回复
(
0
)