听一段材料，回答下面几个小题。
What did the woman do on Friday?
A.She prepared for the exam.
B.She attended a class activity.
C.She had a history lesson.
What is the weather in the desert like at night?
A.Hot and dry.
B.Hot and wet.
C.Cool and dry.
Why is it easy to see different rocks in the desert?
A.There are very few plants.
B.There are too many rocks.
C.There are different colors of rocks.