题干

同学们在做铜与浓硝酸反应的实验时,发现反应后溶液里绿色,而不显蓝色。甲同学认为是该溶液中硝酸铜的质量分数较高所致,而乙同学认为是该溶液中溶解了生成的气体。同学们分别设计了以下4个实验来判断两种看法是否正确。这些方案中不可行的是

A:加水稀释绿色溶液,观察颜色变化

B:加热该绿色溶液,观察颜色变化

C:向该绿色溶液中通入氮气,观察颜色变化

D:向饱和硝酸铜溶液中通入浓硝酸与铜反应产生的气体,观察颜色变化

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A

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根据短文理解,回答下列问题。

    The Internet is becoming more and more important in our life. How much do you know about it? What is the Internet? The Internet is a large, worldwide collection of computer networks. A network is a small group of computers put together. The Internet is many different networks from (A)                 the world. These networks are called the Internet. Once you have learned to use the Internet, you can have a lot of interest in the World Wide Web.

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