Questions 7 to 10 are based on the
following conversation. At the end of the conversation, you will be given 20
seconds to answer the questions. Now, listen to the
conversation.
Why does the professor mention $ 20 bill
A．To confirm that the student is capable of beating Clement. B．To show how sincere he is. C．To give an example of how to run fast. D．To make a joke about the student’s comment.