题目

如图，物体重30N放在斜面上，画出物体对斜面压力的示意图．________   答案：【答案】【解析】在斜面上选取物体与接触面的中点为压力的作用点，过压力作用点画垂直于斜面、带箭头的线段即为压力示意图，如图所示：阅读理解。     Everyone needs friends. We all like to feel close to someone. It is nice to have a friend to talk, laugh,and do things with. Surely, there are times when we need to be alone. We don’t always want people around. But we would feel lonely if we never had a friend.     No two people are just the same. Sometimes friends don’t get along well. That doesn’t  mean thatthey no longer like each other. Most of the time they will make up and go on being friends. Sometimes friends move away. Then we feel very sad. We miss them very much. But we call them and write to them. It could be that we would even see them again. And we can make new friends. It is surprising to find out how much we like new people when we get to know them.                   Families sometimes name their children after a close friend. Many places are named after men and women who have been friendly to people in a town. Some libraries are named this way. So are some schools. We think of these people when we go to these places. There’s more good news for people who have friends. They live longer than people who don’t. Why? It could be that they are happier. Being happy helps you stay well. Or it could be just knowing that someone cares. If someone cares about you, you take better care of yourself.1.The first paragraph tells us _______. A. none needs friendsB. we always need friends around us C. making friends is the need in people's life D. we need to be alone.2.Which of the following is what the writer doesn't say in the passage?A. People will feel lonely if they never have friends. B. People will never see their friends after their friends move away. C. People can know their friends in different ways. D. People like their friends very much if they get to know them.3.People who have friends live longer than people who don't because _______A. they feel happier and are healthy B. they get a lot of help from their friends C. they take better care of themselves D. both A and C4. The main idea of this passage is _______. A. that people are all friends B. that people need friends C. how to get to know friends D. how to name a place