题干

钩码M悬挂在拉力传感器N的下方,如图所示,以下说法中正确的是 

A:M拉传感器N的力与N拉钩码M的力是一对平衡力

B:M受地球的吸引力与N对M的拉力是一对作用力和反作用力

C:M拉N与N拉M的力同时产生,但性质可以不相同

D:M拉N与N拉M的力是同时产生的一对作用力和反作用力

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D

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    Going to college means a lot of changes in their lifestyle for most students. Living in a dormitory remains a major challenge as it means learning how to share space with others who are total strangers.

    While some can live together peacefully, others may face conflicts (矛盾) that need to be worked out. According to a recent survey of students in 12 different universities in Wuhan, only 40 percent of them are satisfied with their dormitory friendships and 35 percent said they kept away from conflicts in the dorm.

    For those living in a dorm for the first time, sharing things, such as a computer or paper towels, can be a source of conflict. Another common conflict is related to different habits. What they are going to do, such as going to bed, watching movies or studying, will also cause a conflict. Sometimes roommates may also have problems when welcoming guests, especially those of the opposite sex.

    However, there are more effective methods to solve problems than screaming at each other. The best way is to talk about an issue before it even becomes a problem. You should treat roommates honestly and directly, and try to work out a solution. And you can also set up rules that everyone can obey. These rules can be written down in an agreement and be put up in a visible (看得见的) place. Students can also outline which items to share and which are for personal use. They can regulate cleaning duties, agree on a time to sleep, and decide on how to receive guests.

    In any discussion it is important to talk with your roommates in a positive way. For example, you can mention your roommates good personality. This can help them understand you better and make them more willing to compromise (妥协).