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问题 选择题

如图所示，烧杯内装有蒸馏水，下部封有半透膜的长颈漏斗内装有淀粉和食盐溶液，漏斗颈内的液面与烧杯内蒸馏水的液面相同。过一段时间后，用碘水和硝酸银溶液分别检测蒸馏水中的物质。整个实验过程中所观察到的现象是

①漏斗颈内的液面下降 ②漏斗颈内的液面上升 ③烧杯内的液体遇硝酸银溶液有白色沉淀生成 ④烧杯内的液体遇碘水变蓝

[ ]

A．①②

B．②③

C．③④

D．①⑤

答案

答案：B

改错题
短文改错。
此题要求改正所给短文中的错误.对标有题号的每一行做出判断:如无错误,在该行右边横线上画一个勾(∧)；如有错误(每行只有一个错误),则按下列情况改正:
该行多一个词:把多余的词用斜线(／)划掉,在该行右边横线上写出该词,并也用斜线划掉.
该行缺一个词:在缺词处加一个漏字符号(∧),在该行右边横线上写出该加的词.
该行错一个词:在错的词下划一横线,在该行右边横线上写出改正后的词.
注意:原行没有错的不要改.
Mrs．Brown was an old lady with just one son who lived far      
away from him. On her 80th birthday, she was sure that even if  
her daughter could not come for a visit, but she would at least
receive a present to her daughter．After all, eighty was a special
birthday, one should not be forgotten．The old lady waited so  
eager that she stood at the front door for a whole day．Her    
daughter didn't show up．However, the old lady got the parcel  
in which there were a printed card along with a cheque．She    
felt very disappointed and she tears the cheque into pieces．    
Everyone but a caring daughter or son could write a cheque．   		1.            
2．         
3．         
4．         
5．         
6．         
7．         
8．         
9．         
10．        

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选择题

一颗在赤道上空距地面高度为36000千米的地球同步实验卫星，绕地运转的速度与地面上对应点的速度比较，正确的是

A．角速度相同

B．角速度不同

C．线速度更小

D．线速度相同
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