B)听下面3段对话。每段对话后有一个小题，从题中所给的A、B、C三个选项中选出最佳选项。每段对话读两遍。
4. For what class hasn't the boy prepared?
A. Biology. B. Chemistry. C. English.
5. How long will they spend riding?
A. Two hours. B. Ten hours. C. Two hours and a half.
6. What is the girl going to do next?
A. Have some fruit salad. B. Buy some fruit. C. Make a fruit salad.
