如图所示为一磁流体发电机示意图，A、B是平行正对的金属板，等离子体（电离的气体，

发布时间：2017-07-29 05:05 │ 来源：www.tikuol.com

题型：选择题

问题：

如图所示为一磁流体发电机示意图，A、B是平行正对的金属板，等离子体（电离的气体，由自由电子和阳离子构成，整体呈电中性）从左侧进入，在t时间内有n个自由电子落在B板上，则关于R中的电流大小及方向判断正确的是（　　）

A．I= ，从上向下

B．I= ，从上向下

C．I= ，从下向上

D．I= ，从下向上

考点：电流路端电压

题型：选择题

阅读理解，完成表格。

     Did you donate (捐献) anything to Sichuan? People all over China and the world are giving help
to the suffering (受苦的) people there after the Wenchuan Earthquake.
     Zha Xiaoxu is a Junior 1 student from Anhui. She began to save money when she was in
kindergarten(幼儿园). Last week, she broke her piggy bank (存钱罐) open and donated all the 700
yuan to Sichuan.
     Han Han is one of the most popular authors (作家) among young people.  Shortly after the
earthquake, he rushed to Sichuan and to help as a volunteer.
     Pop singer Jay Chou had a concert in Chongqing on Saturday.  He decided to give all the ticket
money to Sichuan. Chou has already donated 500 000 yuan to the quake areas.
     Foreign rescuers (救援人员) from Japan, Russia, the Republic of Korea and Singapore are in
Sichuan to help.
     Now more foreign doctors are on their way to Sichuan to look after the injured (受伤的) people.

Person (s)	Career (s)	Donate something to Sichuan
Zha Xiaoxu	a Junior 1 student	donated all the 700 yuan
Han Han	1._____	rushed to Sichuan and to help as a volunteer
2._____	a pop singer	3._____ in Chongqing and decided to give all the ticket money to Sichuan and has already donated 500 000 yuan
Foreign rescuers from Japan, Russia, the Republic of Korea and Singapore are in Sichuan to help.
More foreign doctors are on their way to Sichuan to 4._____

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题型：选择题

下列动物中，属于两栖动物的是（　　）

A．蟾蜍、鳄鱼

B．青蛙、大鲵

C．青蛙、水蛇

D．蜥蜴、蝾螈

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下图是30°N地区几种朝向的窗户内每天可能受到太阳直接照射的时间曲线图。读图，回答1~2题。

1．该地区住宅窗户的下列朝向能使室内冬暖夏凉的是[ ]

A．南

B．东南

C．北

D．东北

2．如果该地区住宅窗户朝向西北，室内受到太阳直接照射时间最短的季节，游客可在[ ]

A．新疆摘葡萄

B．浙江采梅子

C．江西观桃花

D．重庆赏腊梅

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题型：选择题

化湿

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题型：选择题

根据《行政强制法》的规定，对查封、扣押的场所、设施或者财物，下列做法正确的是（）。

A.可以委托第三人保管

B.只能由公安机关保管

C.保管费用由公安机关承担

D.保管费用由当事人承担

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