C

　　Google and Toyota have worked together to create a new smart car. It can run on the road without a driver. It drives itself. The self-driving car hasn’t been on sale to the public, so we don’t know how much it costs. Another thing most people want to know is whether it will be safe enough to run on the road.

　　The self-driving car uses electricity as its power, and it can’t drive very quickly—the top speed would be 25 miles per hour. It is actually controlled by a computer system (系統(tǒng)) on the car. The system keeps on collecting information by some video cameras inside the car and a LIDAR sensor (激光雷達傳感器) on top of it. A computer processes the information and decides what to do. “The self-driving car has only buttons (按鈕) for go and stop, so it’s very easy to use,” an engineer of Google says. “And what’s more, it will make car accidents less and make the world a safer place.” The self-driving car has driven hundreds of thousands of miles in California, and it has only gotten into two accidents by human mistake.

　　According to CNN, self-driving cars will also help to reduce (減少) the number of cars in big cities. “Self-driving cars would be able to send you to the workplace and then pick up another person instead of stopping in a parking lot.”

　　( )30. We don’t know the price of the self-driving car because 　　　　.

　　A. it is on sale only in America

　　B. it isn’t made for sale 

　　C. people can get it for free

　　D. it hasn’t been on sale to the public

　　( )31. The self-driving car can collect information using 　　　　.

　�、賤ideo cameras ②a computer

　　③a LIDAR sensor ④a computer system

　　A. ①② B. ①③

　　C. ①②③ D. ①②③④

　　( )32. According to CNN, self-driving cars will 　　　　.

　　A. send us more quickly to the workplace

　　B. lead to heavier traffic

　　C. improve traffic condition in big cities

　　D. carry more people than a normal car