如图乙所示，一辆小车在A处受到与水平方向成30°角，向右斜上方的大小为60 N的拉力，请用力的示意图画出小车受到的这个拉力．

某中学七年级进行了一次数学测验，参见人数是720人，为了了解这次数学测验成绩，下列所抽取的样本中较为合理的是（　　）

将表面被氧化的铜片和铁片，同时加入足量稀盐酸中，除尽氧化膜。再经充分反应后，溶液中一定含有的金属离子是（   ）

阅读下面短文，然后根据括号内所给汉语意思写出单词的正确形式（每空一词）。
    When I was young and free, I____ （梦想）of changing the world. As I____ （成长）older and wiser, I discovered the world would not change,____ （因此）I shortened my sights and ____ （决定）to change only my country. But it, too, seemed____ （不可能）.Later, I settled for ____ （改变）only my family , those closest to me, but also, they would have none of it. And now as I ____（躺）on my deathbed, I suddenly____ （意识）: If I had only changed ____ （我）first, then by example I would have changed my family.____ （从）their inspiration and encouragement, I would then have been able to better my country and, who knows, I possibly have been changed the world.