题目

“I will think of it.” It is easy to say this, but do you know what great things have come from thinking? Sir Isaac Newton was sitting in his garden when he saw an apple fall from a tree. He began to think and tried to find out why the apple fell. Then he discovered how the sun, moon, and stars are kept in their places. A boy named James Watt sat quietly by the fire, watching the lid of the kettle move up and down. He wanted to find out why the steam in the kettle moved the lid. From that time he went on thinking and thinking. And when he became a man, he improved the steam engine有五本不同的书，其中数学书2本，语文书2本，物理书1本，将书摆放在书架上（1）要求同一科目的书相邻，有多少种排法？(用数字作答)（2）要求同一科目的书不相邻，有多少种排法？(用数字作答)