有关2CuO+C2Cu+CO2↑的反应，说法正确的是[ ] A．C具有还原性 B
题型：选择题
问题：
有关2CuO+C
2Cu+CO2↑的反应，说法正确的是[ ]
A．C具有还原性
B．C发生了还原反应
C．反应前后碳元素的化合价没有改变
D．反应前后固体质量不变
题型：选择题
| 选择恰当的一项，完成对话。 |
| 1. Tom: Jim: Yes. I have three erasers. |
[ ] |
| A. How many erasers are there? B. May I have an eraser? C. Do you have any erasers? |
2.  |
[ ] |
| A. Yes, it is. B. Sure. C. My pleasure. |
| 3. —How much are the donuts? —Two yuan. — |  |
[ ] |
| A. There are four donuts. B. I'll take five donuts. C. I'll take four, please. |
| 4. —How much is this? —Twenty yuan. —Oh ! |  |
[ ] |
| A. Thanks. B. I don't like it. C. That's expensive. |