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
考研
It is hard to track the blue whale, the ocean’s largest creature, which has almost been killed off by commercial whaling and is
It is hard to track the blue whale, the ocean’s largest creature, which has almost been killed off by commercial whaling and is
admin
2011-01-17
31
问题
It is hard to track the blue whale, the ocean’s largest creature, which has almost been killed off by commercial whaling and is now listed as an endangered species. Attaching radio devices to it is difficult, and visual sightings are too unreliable to give real insight into its behavior.
So biologists were delighted early this year when with the help of the Navy they were able to track a particular blue whale for 33 days monitoring its sounds. This was possible because of the Navy’s formerly top-secret system of underwater listening devices spanning the oceans.
Tracking whales is but one example of an exciting new world just opening to civilian scientists after the cold war as the Navy starts to share and partly uncover its global network of underwater listening system built over the decades to track the ships of potential enemies.
Earth scientists announced at a news conference recently that they had used the system for closely monitoring a deep-sea volcanic eruption (爆发) for the first time and that they plan similar studies. Other scientists have proposed to use the network for tracking ocean currents and measuring changes in ocean and global temperatures.
The speed of sound in water is roughly one mile a second--slower than through land but faster than through air. What is most important, different layers of ocean water can act as channels for sounds, focusing them in the same way a stethoscope (听诊器) does when it carries faint noises from a patient’s chest to a doctor’s ear. This focusing is the main reason that even relatively weak sounds in the ocean, especially low-frequency ones, can often travel thousands of miles.
Which of the following is true about the U.S. Navy underwater listening network?
选项
A、It is now partly accessible to civilian scientists.
B、It has been replaced by a more advanced system.
C、It became useless to the military after the cold war.
D、It is indispensable in protecting endangered species.
答案
A
解析
主要依据为第3段第2行的相关内容。
转载请注明原文地址:https://kaotiyun.com/show/qMYi777K
本试题收录于:
GCT工程硕士(英语)题库专业硕士分类
0
GCT工程硕士(英语)
专业硕士
相关试题推荐
Theexperimentconductedbytheresearcherwasmeantto______.Theword"officials"(Line2,Para.4)mostprobablyrefersto
Ihaveheardbothteachersandstudents______wellofhim.
Thepassageismainlyconcernedwiththe______.Accordingtothepassage,whatcausespotassiumandwaterinthemimosatoshi
Thepassageismainlyconcernedwiththe______.Itcanbeinferredfromthepassagethatthemimosaiscalledthesensitivepl
Thebravemanwasgreatlyhonouredwhentheorganizerannounced,"You______amedal!"
SpeakerA:I’vegotafeverandareallybadheadache.SpeakerB:______.
Peoplewenttothesupermarketto______.Whenthemanagertoldherthatshewastheluckycustomer,Mrs.Whitewouldbe______.
AmericanfootballandbaseballarebecomingknowntotheBritishpublicthroughtelevised______fromtheUnitedStates.
Jim:IhaveapairofticketsforanoperaSaturdaynight.Wouldyouliketogo?Cindy:Idon’tthinkso.
Roger:Hurryup!Wedon’thavemuchtimeleft.Dick:______.Westillhavetwohours.Roger:Comeon!Thisismyfirsttimeever
随机试题
SET的成员中被称为付款转接站的是()
“三民主义”中,民权主义的内容是()
对于同一种材料,各种密度参数的大小排列为()。
某期间市场无风险报酬率为10%,平均风险股票必要报酬率为15%,某公司普通股β值为1.2。那么其留存收益的成本为()。
生产烟花爆竹的企业在申请出口烟花爆竹的检验时,应当向检验检疫机构提交()。
进境展览品在展览期间被人购买的()。进境展览品在展览期间被人购买的由()向海关申报进口纳税手续。
根据关税法律制度的规定,下列各项中,关于出口货物关税完税价格的计算正确的是()。
下列关于奥运会说法不正确的是()。
“任何英雄人物的历史作用不能超出他们所处历史条件所许可的范围”。这是()。
Lazinessisasin.Everyoneknowsthatwehaveprobablyallhadlecturespointingoutthatlazinessisimmoral,thatitiswaste
最新回复
(
0
)