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
职称考试
Water The second most important constituent (构成成分)of the biosphere (生物圈)is...
Water The second most important constituent (构成成分)of the biosphere (生物圈)is...
admin
2020-12-24
54
问题
Water
The second most important constituent (构成成分)of the biosphere (生物圈)is liquid water. This can only exist in a very narrow range of temperatures, since water freezes at 0℃ and boils at 100℃. Life as we know it would only be possible on the surface of a planet which had temperatures somewhere within this narrow range.
The earth’s supply of water probably remains fairly constant in quantity. The total quantity of water is not known very accurately, but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers. Most of it is in the form of the salt water of the oceans — about 97 percent. The rest is fresh, but three-quarters of this is in the form of ice at the Poles and on mountains, and cannot be used by living systems until melted. Of the remaining fraction, which is somewhat less than one percent of the whole, there is 10 ?20 times as much stored underground water as there is actually on the surface. There is also a tiny, but extremely important fraction of the water supply which is present as water vapour in the atmosphere.
Water vapour in the atmosphere is the channel through which the whole water circulation (循环)of the biosphere has to pass. Water evaporated (蒸发)from the surface of the oceans,from lakes and rivers and from moist (潮湿的) earth is added to it. From it the
water comes out again as rain or snow, falling on either the sea or the land. There is, as might be expected,a more intensive evaporation per unit area over the sea and oceans than over the land, but there is more rainfall over the land than over the oceans, and the balance
is restored by the runoff from the land in the form of rivers.
Liquid water only exists
选项
A in the center of the earth.
B on the surface of our planet.
C in a very narrow range of temperatures.
D in the costal areas of the earth.
答案
C
解析
转载请注明原文地址:https://ti.zuoweng.com/ti/CdlQKKKQ
相关试题推荐
GoodTableManners Mannersplayanimportantpartinmakingafavorableimpr...
GoodTableManners Mannersplayanimportantpartinmakingafavorableimpr...
RiseinNumberofCancerSurvivors Canceristhesecondleadingcauseofdea...
RiseinNumberofCancerSurvivors Canceristhesecondleadingcauseofdea...
RiseinNumberofCancerSurvivors Canceristhesecondleadingcauseofdea...
RiseinNumberofCancerSurvivors Canceristhesecondleadingcauseofdea...
RiseinNumberofCancerSurvivors Canceristhesecondleadingcauseofdea...
RiseinNumberofCancerSurvivors Canceristhesecondleadingcauseofdea...
RiseinNumberofCancerSurvivors Canceristhesecondleadingcauseofdea...
RiseinNumberofCancerSurvivors Canceristhesecondleadingcauseofdea...
随机试题
下列各项不属于综合安全管理制度内容的是()。 A.承包与发包工程安全管理制度
银行市场细分的作用主要表现在()。[2015年10月真题] A.有利于全面提高
下列关于碳水化合物的描述,错误的是 A.是提供人体热能的主要物质 B.存在于
根据砌块施工工艺要求,多排孔小砌块砌体的搭接长度不得小于()mm。
某项目部承接一项直径为4.8m的隧道工程,起始里程为DK10+100,终点里程为
社区工作对社会的功能包括:
绩效计划结束时,管理人员和员工达成的共识包括( )。
我国《旅游法》规定,国务院建立健全(),对旅游业发展进行综合协调。A.统筹旅游发展机制B.旅游综合协调机制C.部级协调发展机制D.旅游统筹发展机制
当存在期权高估时,交易者可通过卖出股指期货同时买人对应的现货股票进行套利交易,这种操作称为“反向套利”。()
2015年8月8日,甲、乙、丙、丁共同出资设立了一家有限责任公司(下称公司)。乙在公司设立时以机器设备折合30万元用于出资,而该机器设备的实际价值仅为10...