1、第三单元物质构成的奥秘第三单元物质构成的奥秘 单元小结三单元小结三 2018秋季秋季化学九年级上册化学九年级上册 RD B A 铜元素铜元素 铜原子铜原子 碳元素和氧元素碳元素和氧元素 二氧化碳分子二氧化碳分子 1个碳原子个碳原子 2个氧原子个氧原子 钠元素和氯元素钠元素和氯元素 钠离子和氯离子钠离子和氯离子 C D C A C 20 4 金属金属 Ca2 D B C 电子层数电子层数 金属金属 Ne 族族 全文结束！再见全文结束！再见o study whether experiences during teen years would influence adult health.So th
2、ey followed 171 teens,starting when the kids were just 13.They interviewed each one every year for five years，and also spoke to these teens closest friends，who provided additional information about the quality of their friendships.The same 171 people were interviewed again at ages 25,26 and 27.This
3、time,the questions surveyed each persons overall health.When the researchers analyzed the data,they found a strong connection between a teens behavior and adult health.Teens who had close friends grew up to be the healthier adults.Whether teens held back their feelings or expressed them to close fri
4、ends also influenced later health.Those who held back their feelings were more likely to be sick as adults.The connection held up even after the scientists accounted for other possible influences on health.Weight，family income and drug use were all examined.So were mental health issues，such as anxiety and depression.And in these people，such other factors did not explain adult health as well as teen friendships did.Getting along with the crowd may have benefits,says Allen,but there are also drawbacks.Teens who are more independent tend to do better at school and
