完形填空

A train stopped at a small station.An old man on the train looked　1　the window and saw a woman.The woman was selling cakes,and many people from 　2　 train were buying them.The old man wanted　3　a cake,but the old woman was standing far from him.It was raining hard and he　4　 want to go out of the train.

Suddenly he saw a boy.The boy was walking on the platform　5　 from him.“Come here boy,”the old man shouted.“Do you know 　6　each of the cakes is?”“Five cents,”the boy answered.The old man gave ten cents and asked him 　7　two cakes.“One is for me,and　8　is for you,”he told the boy.

Some minutes　9　,the boy came back.He was eating a cake.He gave the old man five cents and said,“Sorry,there was only　10　.”

— How far is it from your home to school?
— It’s around 　　　 walk.
A. ten minute  B. ten minute’s    C. ten minutes’

---How ____ is it from here Ningbo to Xi'an?
　---It's about two ____ flight.
　  

—How far is it from the supermarket to your home?

—It’s about                .

A. 20-minute drive　B. 20-minutes’ drive　C. 20 minute’s drive　D. 20 minutes’ drive