已知命题p：若实数x，y满足x²＋y²＝0，则x，y全为0；命题q：若a>b，则$\frac{1}{a}$<$\frac{1}{b}$，给出下列四个命题：①p∧q；②p∨q；③ $\neg$p；④ $\neg$q.

其中真命题是（  ）．

1. 看图列式计算，正确的是（ ）。
2. 

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   These years, with the development of society(社会), more and more teenagers have suffered from stress. Some of the problems can make them feel very w ____  and unhappy all day. Who can help them? A teacher from a college tried his best to help them. He thought of a lot of w____  to help them. On Monday and Thursday, you can c____  his hotline. Here are some ideas how to keep the young men healthier in every way.
   F____ , it is very important to keep healthy. To get e ____  sleep every day is also necessary. Try to have a healthy d____ every day. Secondly, maybe you are not the top student. It doesn’t m ____ . The most important thing is to work hard. If you try your best, your teachers and parents will understand you. If you have some problems, you should be a____   to talk with your teachers and parents. They can help you. Remember to s____  your happiness and s____   with your good friends. Sometimes you can go out for a walk.
In a word, you can try to make you happy by yourselves. I’m sure you can be happy every day.

美国物理学家密立根（R．A．Millikan）于20世纪初进行了多次实验，比较准确的测定了电子的电荷量，其实验原理可以简化为如下模型：两个相距为d的平行金属板A、B水平放置，两板接有可调电源．从A板上的小孔进入两板间的油滴因摩擦而带有一定的电荷量，将两板间的电势差调节到U时，带电油滴恰好悬浮在两板间；然后撤去电场，油滴开始下落，由于空气阻力，下落的油滴很快达到匀速下落状态，通过显微镜观测这个速度的大小为v，已知这个速度与油滴的质量成正比，比例系数为k，重力加速度为g．则计算油滴带电荷量的表达式为（   ）