根据短文内容，回答下列问题。

     One day Mr Jackson took Paul to his favorite restaurant. It was a French restaurant. The waiter was

from France. But he didn't speak to them in French."Would you like to see the menu?" he asked in a

kind way. "Yes,  please," Mr Jackson said.

     The waiter gave them a menu each.  They studied them. " You can spend only twenty-five dollars,"

Mr Jackson told his son.  The waiter asked Paul, "What would you like, young man?"

     ''How much is the tomato soup?" Paul asked. "Six dollars," the waiter said. "It's very good.''"How

much is the duck with orange?" Paul asked next. "Fifteen dollars" the waiter said."How much is the

chocolate ice cream?"  "Six dollars," the waiter said.

     Paul added(加)it up quickly. Six plus fifteen plus six is twenty-seven. He thought he could have the

duck and the soup, or the duck and the ice cream.  "I'll have the duck and the chocolate ice cream,  

please," he said to the waiter.

     Paul said to his father,  "My meal will cost only twenty-one dollars. Can I keep the other four

dollars?" His father laughed, "No, Paul," he said. "Leave it for the waiter."

1. How did the waiter speak to Paul and Mr Jackson?

2. What did Paul have for dinner?

3. How much did Paul's meal cost?

4. What did Mr Jackson tell Paul to do with the other $4?

5. What does this passage tell us?