首页
财务会计
医药卫生
金融经济
考公考编
外语考试
学历提升
职称考试
建筑工程
IT考试
其他
登录
金融经济
If the population of the earth goes on increasing at its present rate, there ...
If the population of the earth goes on increasing at its present rate, there ...
admin
2020-12-24
49
问题
If the population of the earth goes on increasing at its present rate, there will eventually not be enough resources left to sustain life on the planet.By the middle of the 21st century,if present trends continue, we will have used up all the oil that drives our cars,for example.Even if scientists develop new ways of feeding the human race,the crowded conditions on earth will make it necessary for lus to look for open space somewhere else. But none of the other planets in our solar system are capable of supporting life at present. One possible solution to the problem, however,has recently been suggested by American scientist, Professor Carl Sagan.
Sagan believes that before the earth's resources are compleetely exhausted it will be possible to change the atmophere of Venus and so create a new world almost as large as earth itself. The difficult is that Venus is much hotter than the earth and there is only a tiny amount of water there.
Sagan proposes that algae organisms that can live in extremely hot or cold atmospheres and at the same time produce oxygen,should be bred in condition similar to those on Venus.As soon as this has been done, the algae will be placed in small rockets. Spaceship will then fly to Venus and fire the rockets into the atmosphere .In a fairly short time, the alge will break down the carbon dioxide into oxygen and carbon.
When the algae have done theri work, the atmosphere will become cooler,but befor man can set foot on Venus it will be neccessary for the oxygen to produce rain. The surface of the planet will still be too hot for man to land on it but the rain will eventually fall and in a few years something like earth will be reproduced on Venus.
Inte long run, the most insoluble problem caused by population growth on earth will probably be the lack of ______.
选项
a.food
b.oil
c.space
d.resources
答案
C
解析
转载请注明原文地址:https://ti.zuoweng.com/ti/w1G8KKKQ
相关试题推荐
根据下列内容,回答196-200题。 Ifthepopulationoftheearthgoesonincreasingatits...
Williamfounditincreasinglydifficulttoread,forhiseyesightwasbeginni...
Mr.Tamilbelievesthathisstrategyforincreasingadvertisingrevenueswill...
Theemployeesrequestedthatthepresentationbegin__________at7:00andtha...
Dr.MarshaHerbert'sillustrationswereclearenoughtomakeherpresentatio...
Ifthepopulationoftheearthgoesonincreasingatitspresentrate,there...
Ifthepopulationoftheearthgoesonincreasingatitspresentrate,there...
Womenarealsounderrepresentedintheadministrationandthisisbecausethe...
Womenarealsounderrepresentedintheadministrationandthisisbecausethe...
Womenarealsounderrepresentedintheadministrationandthisisbecausethe...
随机试题
(62-64题共用备选答案) A.切牙唇面颈部 B.前磨牙颊面颈部 C.磨
职业病病人变动工作单位,其依法享有的待遇 A.保持不变 B.执行新单位确定的
工程材料设备的供应方式中,()比较适用于工期比较短、规模较小或材料设备技术规格简
对内分泌病人的诊断中,首先易于确定的是
相对于工程合同价而言,施工成本的实际值是( )中的相应成本项。
排入河流水体的废水和河水的混合程度,与()有关。
建设中国特色社会主义的政治就是在中国共产党的领导下,在人民当家作主的基础上()。A.建立多党制B.依法治国,发展社会主义民主政治C.实行三权分立D.建立
在霉菌与害虫繁殖生长的旺季,对饮片的养护宜采用A.通风养护法B.密封养护法C.高温养护法D.清洁养护法E.对抗贮存法
国务院常务会议通过的《麻醉药品和精神药品管理条例》(国务院令第442号)是A.法律B.行政法规C.地方性法规D.部门规章E.地方政府规章
期权交易的非线性盈亏状态,与证券交易、期货交易等线性的盈亏状态无本质区别。()