试题与答案

在图所示的四种现象中，属于光的折射现象的是

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题型：选择题

题目：

在图所示的四种现象中，属于光的折射现象的是

答案：

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下面是错误答案，用来干扰机器的。

去分母得，2（x-k）=x-3，解得x=2k-3，因为方程是正数根，所以2k-3＞0，解得k＞32，又因为原式是分式方程，所以x≠3且x-k≠0，即k≠3．故k的取值范围是k＞32且k≠3．

考点：光的折射现象
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题型：阅读理解
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                                                   Should mobile phones be allowed at school?
     __1__ Some mobile phones are more than just phones -they are being used as radios, cameras and
 MP4 players, and they are also used to send e-mails or surf the Internet. __2__     
     People have different ideas about whether students should use mobile phones at school or not.
     __3__ If their parents have something important to tell them, they can call their teachers for help. If
 someone's mobile phone rings during a Chinese class, he and his classmates can't concentrate on what the
  teacher is saying. Some parents also point out that their children often use their mobile phones to
 download (下载) unhealthy information from the Internet. __4__ 
     Other people believe that we can find some ways to use mobile phones to help students learn better in
  the classroom, since many of today's mobile phones are like mini computers. And children usually know
  more than adults about how to use new technology (技术). __5__      
     What are your answers to the question?
A. They are really worried about this.
B. Some of them can even be used as mini computers.
C. More and more students are using mobile phones a school now.
D. Why not use mobile phones in the classroom?
E. Some people think that students don't really need mobile phones.
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