市政府为了解决群众看病难的问题，决定下调药品的价格，某种药品，经过连续两次降价后，由每盒20元调至12元．设这种药品平均每次降价的百分率为x，列方程得______．

Passage 1: The Blacks had never been rich enough to spend their summer holidays in a luxurious place. This year, however, Mr. Black made a lot of money and his wife said that she would like to go to Rome for a change. Mr. Black thought it’s a good idea. He said they should stay at a really good hotel while they went around the famous city.They flew to Rome, and arrived at their hotel late one evening. They thought that they would have to go to bed hungrily because no meals were served in cheap hotels where they used to stay. They were therefore surprised when the waiter asked whether they would be having dinner there at night.“Are you still serving dinner now” asked Mrs. Black. “Certainly, madam.” answered the waiter. “We serve it until half past nine.”“What are the time for meals then” asked Mrs. Black.“We serve breakfast from seven to half past eleven in the morning, lunch from twelve to three, tea from four to five and dinner from six to half past nine.”“But that hardly leaves any time for us to see the sights of Rome!” said Mrs. Black in a disappointed voice.

This year Mr. Black ________ a lot of money.

A．printed

B．owed

C．earned

D．borrowed