An English traveler found himself in Norway（挪威） with only enough money to buy the ticket for his journey back home. As he knew that it would take him only two days to get to England, he decided that he could easily spend the time without food. So he bought a ticket and went aboard the ship. The man closed his ears in order not to hear the sound of the lunch bell. When dinner time came , he didn't go to the dining room, saying that he was not feeling very well.

    The next morning he still didn't have breakfast and at lunchtime he again stayed in his room.But at dinner time he was so hungry that he went to the dining room and ate everything the waiter put in front of him. He got ready for a quarrel.

    "Bring me the bill," he said. "The bill, sir?" said the waiter in surprise. "There isn't any bill. On our ship meals are included in the money for the ticket," said the waiter.

因式分解：a²﹣3a=____

31+2sin18°≈____（保留两位小数）

__________ Liu Wei has no hands, he can play the piano very beautifully.

小强今年13岁，是某中学初二学生。最近已有两天不到校了。为此，李老师上门了解情况，知道小强之所以不上学，一是因为家庭经济有困难，没有钱交杂费；二是因为学习基础差，感到读不下去。在动员小强继续上学的谈话中，李老师表示要尽力帮助小强解决所遇到的困难，并向小强及其父亲强调以下儿点：

第一，到学校接受教育对小强个人的成长很重要；

第二，小强到不到学校接受教育不仅仅是个人的事；

第三，小强不到学校接受教育是违反有关法律规定的。