Mrs. Herry lived in a city of America. Her husband had a few big stores. Two years ago the rich shopkeeper was hit(被撞) in a traffic accident. He was taken to a hospital at once, but the doctors could not save him and he soon died. He left his wife plenty of money, but the woman was very sad. She sent(打发) all servants(佣人), cooks and drivers away and began to live alone. But she took good care of Bobby, her husband's dog. And she can't leave him now.
      One summer afternoon, Mrs. Herry went to do some shopping. Suddenly it began to rain, so she had to take a bus. As soon as she got on, she said to the driver, “Can you look for a seat for my dog if I buy a ticket for him, Sir? ”
    The driver had a look at the dog and found its legs were very dirty. He said, “Of course I can, Madam. But he must sit on the seat like you do!”
根据短文内容，回答问题。

求证：直线DF与⊙O相切

在我国社会生活中有许多规定，如考场严禁学生作弊，严禁携带易燃易爆危险品上车等。每位公民都必须遵守这些规则，因为（   ）​

浏览名人长廊，领悟文明进步。
杰出人物在人类文明发展进程中起到了重要作用，根据图片回答问题：

请回答：
（1）图一人物是谁？写出他的一部代表作品。
（2）图二人物是谁？说说他的重大历史贡献。
（3）图三人物颁布的法律文件意义是什么？
（4）图四人物为人类作出的杰出贡献是什么？ 
（5）概括四位人物在世界历史上所起到的共同作用。