It's seven forty in the morning. The children are coming into the classroom. A girl is opening the windows. Some are laughing and talking. Some are listening to them. Some are reading books. Some are doing their homework.

    Miss Gao is standing behind the teacher's desk. She is writing on the blackboard. Sue and Han Mei are wearing their new dresses today. Ann is cleaning her desk. Mike is helping her. They all look happy.

What are Bill and Lin Tao doing? Oh, dear! They are still playing basketball!

下列关于材料的说法中，正确的是（　　）

判断对错．

整数都可以看成分母是1的假分数．

有五个完全相同的杯子，其中一个盛满开水，其他杯中没有水，仅利用杯子的吸热作用，将开水的温度降低，则下列方法中效果最好的是（　　）