首页
登录
职称英语
How much of the earth’s water can man really use? [br] [originaltext] The w
How much of the earth’s water can man really use? [br] [originaltext] The w
游客
2023-11-15
63
管理
问题
How much of the earth’s water can man really use? [br]
The world is not only hungry, but thirsty for water. That may seem strange to you, since nearly 75% of the earth’s surface is covered with water. But about 97 % of this huge amount is sea water, or salt water. Man can only drink and use the other 3%-tile fresh water from rivers, lakes, underground, and other sources. And we cannot even use all of that, because some of it is in the form of icebergs and glaciers. Even worse, some of it has been polluted.
However, this small amount of fresh water is still enough for us. But our need for water is increasing rapidly. Only if we take steps to deal with the problem now can we avoid a severe world-wide water shortage later on.
One of the first steps is to develop ways of reusing it. Today water is used only once and then discharged into a sewer system, and it eventually returns to the sea or runs into underground storage tanks. But it is possible lo pipe used water to a purifying plant. There it can be filleted and treated with chemicals so that it can be used again.
But even if every large city purified and reused its water, we would still not have enough.
All we’d have to do to make use of the sea water in, the world is to remove the salt. If we take these steps we’ll be in no danger of drying up!
选项
A、Water can be used only once.
B、Used water can be recycled.
C、Recycled water is unfit for drinking.
D、Only rain water is drinkable.
答案
B
解析
录音稿:But it is possible to pipe used water to a purifying plant.There it can be filtered and treated with chemicals so that it can be used again.
转载请注明原文地址:http://tihaiku.com/zcyy/3189283.html
相关试题推荐
WhatchangeshappenedattheAcademyAwards?[br][originaltext]Thisyear,
WhatchangeshappenedattheAcademyAwards?[originaltext]Thisyear,somet
Whatisafrankfurter?[br][originaltext]Mostpeopleknowwhatahotdogis
Whatisafrankfurter?[br][originaltext]Mostpeopleknowwhatahotdogis
Whatisafrankfurter?[originaltext]Mostpeopleknowwhatahotdogis.It’s
Whatistheconversationmainlyabout?[br][originaltext]W:Dr.Smith?Thisis
WhichofthefollowingisCORRECTaboutthenewlibrary?[br][originaltext]M:
WhichofthefollowingisCORRECTaboutthenewlibrary?[br][originaltext]M:
TheJapanesebullettrains______.[br][originaltext]Foryearsnow,the
TherelationshipbetweenEuropeandIndiaisbasedon______.[originaltext]
随机试题
Formilesaround,theneighborhoodswereemptyandsilent.Storesweredark,
YoungpeopleintheUnitedStatesarefallingbehindtheiroverseaspeersin
[originaltext]M:Hey,nicetoseeyouagainafterthelongvacation.Howareyo
参与免疫应答的细胞表面都具有A.膜表面免疫球蛋白 B.补体受体 C.抗原识别
某单位从银行借入一年期的借款,银行采用贴现法收取利息,其名义利率是每年15%,并
无牙颌牙槽嵴严重吸收的患者排牙时宜工牙宜采用A.解剖式牙 B.半解剖式牙 C
如图所示的四种用具在正常使用的过程中,属于省力杠杆的是:()A. B.
简述市场经济的基本特征。
水利工程生产安全重大事故隐患判定方法分为()。A.事故树法 B.直接判定
A.深吸气末S分裂,尤见于青少年 B.主动脉瓣关闭迟于肺动脉瓣关闭 C.肺动
最新回复
(
0
)