题干

电池使用说明中都有一条提示:“请一次性更换所有电池,避免新旧电池混用”.小海同学用所学物理知识设计了一个实验方案研究为什么要这样提示.小海按照图组装电路,将同型号的两节新电池串联、一新一旧两节电池串联和一节新电池分别接在A、B间,闭合开关S后记录电压表示数.请将空白处补充完整.

电源

S闭合时电压/V

两新

2.7

一新一旧

1.2

一新

1.4

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keep,   share ,   help,   be,   much

    Students these days often have a lot of worries. Sometimes they have problems with their schoolwork, and sometimes with their friends. What can they do about this? Some people think the worst thing is to do nothing. Laura Mills, a teenager from Washington, agrees.    "Problems and worries are normal in life," says Laura. "But I think talking to someone ____ a lot. If we don't talk to someone, we'll certainly feel worse "

    Laura once lost her purse, and worried for days. She was afraid to tell her parents about it. She even walked three miles to school each day because she didn't have any money. She just ____ thinking, "If I tell my parents, they'll be angry!" But in the end, she talked to her parents and they were really understanding. Her dad said he sometimes made careless mistakes himself. They got her a new purse and asked her ____ more careful. "I will always remember____ my problems in the future!" Laura says.

    Robert Hunt advises students about common problems. He feels the same way as Laura. "It is best not to avoid our problems. We should always try to solve them." He thinks that you can first find someone to talk to. This person doesn't need to be an expert (专家) like himself. Students often forget that their parents have ____ experience than them, and are always there to help them.

    In English, we say that sharing a problem is like cutting it in half. So you're halfway to solving a problem if you talk to someone about it!