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
72
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
ThestatisticsI’vecitedandthelivingexamplesarealltoofamiliartoyou
Thelegallimitfordrivingafterdrinkingis80milligramsofalcohol(酒精)in
UsingBestBuyExpressServiceiseasy.JustfollowthePurchasingGuide.Or
智能建筑系统中,采用计算机、网络通信和自动控制技术,对建筑物中的设备进行自动化监
当杆件AB的A端的转动刚度为3i时,杆件的B端为( )。A、自由端 B、固定
能引起抗利尿激素分泌变化的血浆渗透压最低变化幅度是A.1% B.2% C.3
A.火焰灭菌法 B.干热空气灭菌 C.流通蒸汽灭菌 D.热压灭菌 E.紫
案例四: 一般资料:求助者,男性,38岁,公司部门经理。 案例介绍:求助者半
面质技术也称()。多选A.质疑 B.对抗 C.指责 D.正视现实
(2018年真题)下列属于非概率抽样的是()。A.等距抽样 B.判断抽样
最新回复
(
0
)