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问题 选择题

2007年8月24日下图所示国家发生的特大森林火灾，被列为近15年来世界上最严重的森林火灾之一。据此回答1~2题。

1、造成该国此次森林大火的主要气候原因是[ ]

A、季风一干热

B、西风一大风

C、信风一大风

D、副高一干旱

2、实时监测森林火情，直接应用的现代技术为[ ]

A、地理信息系统

B、遥感技术

C、全球定位系统

D、数字地球技术

答案

1、D

2、B

完形填空

阅读下面材料，在空白处填入适当的内容（每空不多于3个单词）或括号内单词的正确形式。

China's Tea Villages

In most Chinese tea villages, March is the time of year in ___小题1:___ locals start to pick and process tea. The usually quiet villages suddenly become busy centers of activity, as people take out special tools and prepare ___小题2:___ tea processing. In some villages, local residents hold traditional ceremonies, __小题3:___ (thank) heaven for its blessing. The price of tea ___小题4:___ (pick) in March is extremely high because __小题5:___ is fresh, tender and contains multiple trace elements.

China ___小题6:___ (be) famous for tea production since ancient times. Of the goods transported and traded along __小题7:___ Old Silk Road linking China to the Middle East and Europe, the importance of tea was matched only by silk. China produces Oolong, black, green, white, yellow __小题8:___ dark (aka post-fermented) tea. The Oolong, green and black __小题9:___ (vary)are most notable for their high quality.

Most of China's tea villages are found in remote mountainous areas in the country's south and southwest, __小题10:___ the beautiful scenery is often hidden under clouds.
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计算题

如图所示，轨道ABCD的AB段为一半径R=0.2的光滑圆形轨道，BC段为高为h=5的竖直轨道，CD段为水平轨道。一质量为0.1的小球由A点从静止开始下滑到B点时速度的大小为2/s，离开B点做平抛运动（g取10/s2），求：

（1）小球离开B点后，在CD轨道上的落地点到C的水平距离；

（2）小球到达B点时对圆形轨道的压力大小？
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