问题
多选题
| 当两个分子间的距离r=r0时，分子处于平衡状态，设r1＜r0＜r2，则当两个分子间的距离由r1变到r2的过程中（ ） A．分子力先减小后增加 B．分子力先减小再增加最后再减小 C．分子势能先减小后增加 D．分子势能先增大后减小 |
答案
BC
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| 当两个分子间的距离r=r0时，分子处于平衡状态，设r1＜r0＜r2，则当两个分子间的距离由r1变到r2的过程中（ ） A．分子力先减小后增加 B．分子力先减小再增加最后再减小 C．分子势能先减小后增加 D．分子势能先增大后减小 |
BC
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There are many ways to save the environment if you would like. In this passage, you can find some ways. Plant more trees. Choose a right 小题1:________ near your house or workplace. 小题2:________ there’s any rule stopping you growing trees in that area, go ahead and grow trees. Plant a tree every month and小题3:________ your friends and classmates to join you. Have more and more trees 小题4:________ and there will come a day when you have green land thanks to your hard work. Walk more and drive less. Choose to walk 小题5:________ drive your car. Walk or ride a bicycle to work if it’s not very far. Not only cycling but walking is good exercise. And each time you avoid using your car, you’re doing something 小题6:________ to cut down air pollution. You are saving fuel, saving money and keeping fit as well. Save water. Water is very important for living things. It’s 小题7:________ who use and pollute it. The simplest way to save water is turning 小题8:________ water taps after use. When you visit a beach, make sure that you don’t throw waste around. Do not pollute rivers 小题9:________ dropping garbage or other waste. Water is so precious, so we 小题10:________ waste or pollute it. |