题目

Every year, more books on happiness are published. And every year, more people feel depressed because they do not see themselves as happy. They don’t remember or know what it feels like, and instead, they feel guilty that they aren’t as happy as everyone says they should be. This is really a sad state of emotional affairs. The books, blogs, YouTube videos and advice columns (专栏) will tell you that if you read, exercise, stay busy, help others, and increase your intimacy (亲密) every day, then you too can be happy. The simple truth is that no one can be happy all the time. That doesn下列实验操作正确的是A．检验某溶液中是否含有甲醛：在盛有2mL10％硫酸铜溶液的试管中，滴加4~8滴10％的氢氧化钠溶液，混合均匀，滴入待检液，加热B．实验室制乙烯：将浓硫酸与无水乙醇按体积比3∶1混合后迅速加热至170℃C．制取溴苯：将铁屑、液溴、苯充分混合后加热D．提取溶解在水中的少量碘：加入植物油振荡、静置、分层后取出有机层再分离