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问题 选择题

关于反应2SO2+O22SO3，在一定条件下达到平衡状态，再加入一定量的18O2，则建立新平衡时，含有18O的物质是(假定原平衡体系中不含18O) [ ]

①二氧化硫 ②氧气 ③三氧化硫

A．①②

B．②③

C．①②③

D．①③

答案

答案：C

阅读理解

阅读下面的材料。然后根据材料内容回答问题。

Every year there is the Spring Festival in China. Usually it is in January or February. It's the most important festival in China. So before it comes, everyone has to prepare things. They buy beef, pork, chicken, fruit and many other things. And they often make a special kind of food called "dumpling". It means "come together" in Chinese. On the day before the festival, parents buy new clothes for their children and children also buy presents for their parents. On the festival eve, all the family members（成员）come back to their home. This is a happy moment. They sing, dance and play cards. When they enjoy the meal, they give each other the best wishes for the coming year. They all have a good time.

小题1:When is the Spring Festival in China?

小题2:What does "dumpling" mean?

小题3:What do parents usually buy for their children before the festival?

小题4:What do the family members usually do on the festival eve?

小题5:Is the Spring Festival very important in China?
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填空题

反射界面空间校正中所指的三个深度分别是：（）；视铅垂深度；（）
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