阅读理解。 The 100-kilogram blue solar car invented by 10 students at Southwest University's College of Engineering and Technology in Chongqing has a top with four solar panels that charge the battery that powers the auto. Its speed is between 30-40 kilometers per hour and when fully powered the car can be driven as far as 50 kilometers. 'The car is easy to drive. A person without any driving experiences could learn to use it in several minutes. It fits for campus and the golf course,' said He Daijie, the leader of the invention team and a senior at the college. Or if one prefers it can be turned into moped scooter (电动助力车), he said. Four students at Shenyang University of Technology in Liaoning Province invented a door light powered by electrical energy produced by opening and closing a door. When people open or close a door, the door produces mechanical energy that could be turned into electrical energy. After numerous tests for several months, the students fixed a joint lever above the door that connects the door and a speeding gear case to drive a generator attached to the door and send energy to storage cells. The storage cells provide electrical energy for the light. A college student's dorm door is opened and closed about 60-100 times a day, which could produce 160- 280 milliamps of electrical energy. It takes 160 milliamps to keep a light working for at least 10 hours, said Xia Yingbiao, one of the invention team members and a mechanical designer and manufacturing and automation junior. If these lights were used with the invention at the entrances in Shenyang schools, about 700,000 kilowatt hours a year would be saved, the team said. The university is applying patents for the invention. 1. Where is the first invention mainly designed to use? A. On the traffic roads. B. In parks and gardens. C. On campus and the golf course. D. In kindergartens 2. The car is charged ____. A. with solar panels at the solar station B. with solar panels on its top C. through the wires at public places D. through the wires at home 3. Where does the power of door light come from? A. Electricity through wires. B. Mechanical energy by opening and closing the door. C. Sun panels on the building top. D. Batteries charged before being used. 4. From the two inventions, we can see that ____. A. students could design for the future B. inventions are not so difficult C. these inventions are valuable but not practical D. inventions can't lack knowledge and money