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问题 选择题

下列说法正确的是（　　）

A．相似三角形一定全等

B．不相似的三角形不一定全等

C．全等三角形不一定是相似三角形

D．全等三角形一定是相似三角形

答案

A、相似三角形大小不一定相等，所以不一定全等，故本选项错误；

B、不相似的三角形一定不全等，不是不一定全等，故本选项错误；

C、全等三角形一定是相似三角形，故本选项错误；

D、全等三角形是相似比为1的相似三角形，所以一定是相似三角形，正确．

故选D．

阅读理解

Many children think mobile phones are cool. They come in fun colors and let you talk with friends anytime and anywhere.

In the U.S., more than 90 million people use mobile phones. Many of these people are children. For children, mobile phones are more than phone calls. They are fashionable.

Most mobile phone users don’t think about the health problems caused(引起) by mobile phones. Some scientists say that mobile phones give off radiation(辐射) that might be bad for the users. One newest study shows that mobile phone radiation might raise(增加) a person’s chance of getting some kinds of cancer(癌症). Other scientists say mobile phones don’t’ threaten people’s health. They say that they have not found any link(联系) between phone use and cancer.

Scientists say that people can protect (保护) themselves from mobile phone radiation. One way is to use a headset(耳机). Or people can make shorter call.

小题1:Many children like mobile phones because they think mobile phones are _________.

A．cool

B．small

C．cheap

D．their toys小题2:Many of the mobile phone users in the U.S. are ___________.

A．girls

B．boys

C．scientists

D．children小题3:Some scientists think mobile phones aren’t _________ for users health. They causes some kinds of cancer

A．bad

B．good

C．wrong

D．helpful小题4:The underlined word “threaten” in the passage means ____________.

A．威胁.

B．担心

C．治疗

D．证实小题5:What should people do to protect themselves from mobile phone radiation?

A．Make longer calls

B．Use a headset

C．Make shorter calls

D．Both B and C
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综合

阅读材料并回答问题。（11分）

材料一:“一条大河波浪宽，风吹稻花香两岸,我家就在岸上住……”

材料二:左图为我国江南丘陵地区某城市平原图，右图为美国--区域的农业地域图。

（1）材料一中“大河”两岸的农业地域类型是             。（1分）

（2）左图中城市周围A 、B 、C、 D四个区位安排花卉业、果园、乳牛业、粮食或经济作物的生产，应如何对应布局？（4分）

花卉业________； 果园_________；乳牛业_________；粮食或经济作物___________。

（3）该地区90年代初期曾大规模栽桑养蚕，后因国际市场价格大跌，而银杏叶提取物价格看好，农民就毁桑发展银杏采叶圃然而5年后市场上银杏叶提取物需求量锐减，农民又开始刨银杏树。导致上述现象产生的区位因素是______________。（1分）

（4）材料二右图美国区域图显示了美国农业生产______________化（1分），值得我国借鉴。试分析影响①农业区形成与发展的主要区位因素。（4分）
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