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冰的体积变大还是变小?

在物理小组活动的时候,小明提出了这样一个问题:“水在结冰的时候体积如何变化?”小刚立即做出了回答:“根据物体热胀冷缩的性质,水结冰时的体积当然是变小的。”但小红提出了相反的意见:“如果体积变小的话,那么冰的密度会变大,冰将会沉入水中。但事实上冰会浮在水面上,所以体积应变大。”

到底谁对谁错呢?小刚提出了通过实验去解决这个问题,并提出了自己的实验方案:“在小药瓶中装满水,放到冰箱中使水完全凝固,然后看看冰面是下降了还是升高了,不就行了吗?”大家都赞同这个方法,于是他们立即动手实验。于是他们在小容器中装满水后放入冰箱让它结冰,结果发现冰面是向上凸起的。

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    Moving into a new home in a new neighborhood is an exciting experience. Of course, you want to make sure that you become an accepted and valuable part of your new neighborhood. The easiest way to accomplish this is to make sure you conduct yourself as a good neighbor should.____

    Perhaps one of the most important things you can do as a good neighbor is to keep your property(房产) neat, clean, and in good repair. ____By choosing to keep the outside of the home in great shape, you will help to improve the look and feel of the area.

    Second, take the overall appearance of the neighborhood seriously. When going for a walk. Take along a small garbage bag. ____This small act will let your neighbors know that you care about the area.

    ____ If a neighbor is going to be out of town, offer to collect mail and newspapers. If a neighbor suffers an illness, offer to do the grocery shopping. Let them know you are there to help in any way this acceptable, while still respecting the privacy of your neighbor.

    ____By following the basic rules of respecting others, taking care of what belongs to you, and taking pride in the appearance of the neighborhood in general, you will quickly become a good neighbor that everyone appreciates.

A. In general, keep an eye on their property while they are gone.

B.A good neighbor is also one who likes to help out in small ways.

C. Being a good neighbor is more or less about considerate behavior.

D. Sometimes neighbors may go to the supermarket together to do shopping.

E. Should you come across waste paper thrown out of a passing car, pick it up.

F. People tend to lake pride in keeping everything in their street fresh and inviting.

G. Here are a few tips to help you win over everyone in the neighborhood quickly