Is this ____ (Amy, Amy's ) desk?

通读短文，掌握其大意，然后在各小题所给的三个选项中，选出一个最佳答案。

    Sam is my new classmate. He is 1 American boy. He is from New York. He is thirteen.

    Sam often gets up at about 6: 30 on2. And he often 3 a cup of tea, an egg and some bread for his breakfast. Then he goes to school at 7: 30 a.m. and gets there 4 8: 00 a.m. . They have four classes in the morning and two in the 5. At 3: 50 p.m. they play games. He studies hard and studies 6. He likes English and is good at it. He teaches us 7 and we teach him Chinese. He can speak a little Chinese now, but not 8 . Mike is his good friend. They go home together(一起). He does 9 homework at home, but sometimes at school. On Saturday and Sunday, he likes 10 football games on TV. He often goes to bed at about nine.

  22.62÷7.2-(12.7-8.9)=____

（得数保留两位小数）