首页
登录
职称英语
[originaltext]The vast oceans of the world are dark, deep and mysterious places
[originaltext]The vast oceans of the world are dark, deep and mysterious places
游客
2023-07-09
41
管理
问题
The vast oceans of the world are dark, deep and mysterious places where eyesight counts for little as soon as you venture very far beneath the surface.
For humans, who live in a world dominated by visual stimuli, to exist in such conditions would be impossible. But for whales and dolphins that live in the ocean or, in the case of a few species, muddy rivers, the darkness is unimportant. What is important to them is sound.
Sound is an efficient way to transmit and sense information, especially as it travels five times faster through water than through air. If humans shout to someone, it is unlikely that they will be heard a kilometer away. But if a whale shouts in an ocean channel, another whale may hear it tens, if not hundreds, of kilometers away.
Whales and dolphins use sound in two ways: for communication and for echolocation. Dolphins and toothed whales communicate through a wide variety of high-frequency sounds.
But as well as using sounds to communicate, toothed whales and dolphins also rely on echolocation to learn about their immediate environment, including prey that might be waiting nearby. They produce intense short broad-band pulses of sound in the ultrasonic range. These clicks are brief, typically less than one millisecond long — but they are repeated many times each second.
Questions 26 to 28 are based on the passage you have just heard.
26. For whales and dolphins, which sense is most important?
27. How much faster does the sound travel in the water than in the air?
28. How do the dolphins and toothed whales communicate?
选项
A、Six times.
B、Five times.
C、Three times.
D、Two times.
答案
B
解析
选项表明,本题考查倍数或次数。短文中提到,声音在水中传播的速度是在空气中传播速度的5倍,故答案为[B]。
转载请注明原文地址:https://tihaiku.com/zcyy/2821960.html
相关试题推荐
[originaltext]IfyouplantoremainintheUnitedStatesforanylengthof
[originaltext]IfyouplantoremainintheUnitedStatesforanylengthof
[originaltext]In1968,thecityofPhiladelphia,Pennsylvania,hadaproble
[originaltext]ChristmasisAmerica’smostpopularholiday.Somepeopleatte
[originaltext]ChristmasisAmerica’smostpopularholiday.Somepeopleatte
[originaltext]M:Lesley,againandagainthesedaysweheartilewords"he’son
[originaltext]M:Lesley,againandagainthesedaysweheartilewords"he’son
[originaltext]M:Hello,professorJohnson.W:Hello,Tony.Sowhatshallwewor
[originaltext]M:Hello,professorJohnson.W:Hello,Tony.Sowhatshallwewor
[originaltext]M:Hi.Susan!HaveyoufinishedreadingthebookProfessorJohnso
随机试题
曲棍球()滑雪[br]花样滑冰()山地车D、K
LookattheintroductiontoWestThamesCollegeonthefollowingpageandatthe
A—Above-the-lineadvertisingJ—MailorderadvertisingB—Lightbo
(2011年)下列有关税收立法程序的说法,正确的是( )。A.通过的税收法律由全
从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性: A.如
能用珍珠母而不能用刺蒺藜治疗的病症是A.头晕目眩 B.惊悸失眠 C.小便不利
[多选题]属于标准分数常模的包括( )。A.百分等级 B.T分数 C.比
关于绝经激素的治疗,下列说法正确的为A.替勃龙具有更高的乳腺安全性 B.围绝经
某工程竣工验收阶段,承包人于3月1日向工程师送交了竣工验收报告,发包人于3月15
根据《建设工程项目管理规范》(GB/T50326-2017),风险等级较高,风险
最新回复
(
0
)