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问题 选择题

实验室用下列两种方法制氯气：①用含HCl  146g的浓盐酸与足量的MnO2反应；②用87gMnO2与足量浓盐酸反应．所得的氯气（　　）

A．①比②多

B．②比①多

C．一样多

D．无法比较

答案

答案：B

单项选择题

在我国，发明专利的保护期限为 (33) 年，实用新型专利和外观设计专利的期限为 (34) 年。中国专利局授予的专利权适用的范围为 (35) 。商业秘密受保护的期限是 (36) 年。

A．10

B．20

C．30

D．40
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填空题

用所给单词的正确形式填空。

1. Some people believe that dinosaurs are still              (live) today.

2. Jenny and Danny put all the              (sort) garbage into some bags for recycling.

3. They have              (repair) the broken car.

4. It's fun              (fill) the bottle with something special.

5. The Great              (lake) are the largest bodies of fresh water in the world.

6. The two villages              (connect) by a new road are not far from my hometown.

7. He is very               (humor).

8. They built               (factory) in Germany and France in the 1890s to make cars.

9. He asked me              (hold) on while he left the telephone to get a pen.

10. You'd better not              (do) that.

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