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
专升本
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
2022-06-23
27
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 43 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 part of 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 planned 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.
The underwater listening system was originally designed________.
选项
A、to trace and locate enemy vessels
B、to monitor deep-sea volcanic eruptions
C、to study the movement of ocean currents
D、to replace the global radio communications network
答案
A
解析
根据第三段“…as the Navy starts to share part of its global network of underwater listening system built over the decades to track the ships of potential enemies. ”可知,水下监听系统最初是为了追踪潜在敌人的船只。故选A。
转载请注明原文地址:https://kaotiyun.com/show/2tQD777K
本试题收录于:
英语题库普高专升本分类
0
英语
普高专升本
相关试题推荐
认识是在实践中主体对客体的能动反映,这是
Manyayoungpersontellsmehewantstobeawriter,Ialwaysencouragesuchpeople,butIalsoexplainthatthere’sabigdiff
Thereisanotherconversationwhichfromourpointofviewisequallyimportant,andthatistodonotwithwhatisreadbutwit
Peoplefoundtotheirhorrorthattwo-thirdsoftheadultpopulationinthatareahad________AIDS.
Manypeoplehavetheexperiencethatgettingupinthemorningissodifficultandpainful.Thismightbecalledlaziness.ButD
ShewassurprisedtofindalltheseCDsandshepickedoneupandsatdownonthebedandshestartedtoopenone.
Commonsensewouldtellusthatphysicallyactivechildrenmaybemorelikelytobecomeactiveandhealthyadults.IntheUnited
Thecommercialcenter________willbethemostmagnificentoneinthecity.
Whatisthepriceofmixedfruits?
Whatisyourfavoritecolor?Doyoulikeyellow,orange,orred?Ifyoudo,youmustbeanoptimist(乐观主义者),aleader,anactive
随机试题
A.表面活性物质B.胸膜腔内压C.肺内压D.弹性阻力E.顺应性吸气末与呼气末和大气压相等的是()。
在研发过程中,科研机构和人员不仅需要大型仪器设备,也需要文献、数据、实验动物及其组织样本库等资源。一个调研课题的统计表明,各方对科技文献和数据的需求居于首位。目前这些重要资源大量沉淀在高校和研究院所,需要使用它们的单位(尤其是企业)无法__________
蒙田认为,正确的教育的目的应当是培养()
健康教育的目的是
皮下注射的进针角度为
设A是3阶矩阵,P=(α1,α2,α3)是3阶可逆矩阵,且P-1AP=若矩阵Q=(α1,α2,α3),则Q-1AO=()。
企业为职工缴纳的基本养老保险金、补充养老保险费,以及为职工购买的商业养老保险,均属于企业提供的职工薪酬。()(15.1)
我国税务机关根据纳税人的生产经营状况对小型无账证的个体工商户可以采取()征收税款。
有条理地概述这些资料所反映的主要内容,字数不超过200字。要求:全面,有条理,有层次。[参考例文] 容留日本客集体嫖娼是严重的犯罪行为 2003年9月18日前后,广东省珠海市国际会议中心大酒店竟发生了容留近500名娱乐场所陪
对下列二叉树进行前序遍历的结果是
最新回复
(
0
)