six seven eight nine ten — 英语阅读题

Read and answer. 阅读短文，回答问题。 Hello, I'm Kitty. Today is our School Open Day. Look at Classroom 3. There are ten desks in it. On the desks, you can see nine bags. There are eight books on the teacher's desk. Seven pencils are in a blue box. Near the door, there are six chairs. How many balls? Oh, there is only one ball under the desk. I like our classroom! Question: How many books are on the teacher's desk?