如图所示电路,电源电压不变。当开关S闭合、S1与S2断开时,电流表示数为I1,电

题型:选择题

问题:

如图所示电路,电源电压不变。当开关S闭合、S1与S2断开时,电流表示数为I1,电压表示数为U1;当开关S、S1、S2都闭合时,电流表示数为I2,电压表示数为U2。则下列说法正确的是

[ ]

A.l1>I2   UI>U2

B.l1<I2   UI<U2

C.l1>I  UI<U2

D.l1<I2   UI>U2

考点:电流的测量,电流表的使用及读数方法电压的测量,电压表的使用
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生活污水管道一般采用()。

A.铸铁管

B.塑料管

C.混凝土管

D.带釉陶土管

E.钢管

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地球上的水在不停地运动着、变化着,形成一个巨大的循环系统,如图所示的两个实验分别表示这个循环系统中的两个变化,图甲是在热水上方放置了一个装有冰块的容器,它可以模仿_______(选填“雨”、“雪”或“冰”)的形成过程;图乙是在锥形瓶中放入少量碘粒,再在靠近碘粒的上方悬一根棉线,通过对碘微微加热来模仿_______(选填“雨”、“雪”或“冰”)的形成过程.

题型:选择题

结合小说《变色龙》内容分析对比手法及其作用。

_________________________________________________________

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中 * * 党的十六大指出:必须把可持续发展放在十分突出的地位,坚持三大基本国策就是坚持( )。

A.科教兴国

B.环境保护

C.资源保护

D.计划生育

题型:选择题

The "standard of living" of any country means the average person’s share of the goods and services which the country produces. A country’s standard of living, (1) , depends first and (2) on its capacity to produce wealth." Wealth" in this sense is not money, for we do not live on money (3) on things that money can buy. "Goods" such as food and clothing, and "services" such as transport and " (4) ". A country’s capacity to produce wealth depends upon many factors, most of (5) have an effect on one another. Wealth depends (6) a great extent upon a country’s natural resources. Some regions of the world are well supplied with coal and minerals, and have a fertile soil and a (7) climate; other regions possess none of them.

Next to natural resources (8) the ability to turn them to use. China is perhaps as well (9) as the USA in natural resources, but suffered for many years from civil and (10) wars, and (11) this and other reasons was (12) to develop her resources. (13) and stable political conditions, and (14) from foreign invasion, enable a country to develop its natural resources peacefully and steadily, and to produce more wealth than another country equally well (15) by nature but less well ordered.

A country’s standard of living does not only depend upon the wealth that is produced and consumed (16) its own borders, but also upon what is indirectly produced through international trade. (17) , Britain’s wealth in foodstuffs and other agricultural products would be much less if she had to depend only on (18) grown at home. Trade makes it possible for her surplus manufactured goods to be traded abroad for the agricultural products that would (19) be lacking. A country’s wealth is, therefore, much influenced by its manufacturing capacity, (20) that other countries can be found ready to accept its manufactures.

2()

A.primary

B.principal

C.foremost

D.uniquely

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