单项选择题
M: Susan, just check the map and see how far we have to 20 before we get to the town.
W: I think we’ll have to go another twenty miles. Our speed is now 40 miles per hour, so we’ll get there pretty soon.
A. In about 40 minutes.
B. In about 30 minutes.
C. In about 20 minutes.
D. In about 10 minutes.