飞机的起飞过程是从静止出发，在直跑道上加速前进，等达到 一定速度时离地．已知飞机加速前进的路程为1 600 m，所用的时间为40 s．假设这段运动为匀加速运动，用a表示加速度，v表示离地时的速度，则 [ ]
A．a=2 m/s2，v= 80 m/s
B．a=1 m/s2，v= 40 m/s
C．a=80 m/s2，v= 40 m/s
D．a=1 m/s2，v= 80 m/s
答案：A
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| The 50-year-old farmer (农民), Wu Yulu is quite different from the others at his village. He is the 1 of 38 handmade robots. He has been 2 to show his robots at the opening ceremony of the Shanghai World Expo. Born in a 3 family, he did not have the opportunity to go to school. But even as a child, he knew he wanted to make machines. “I think 4 machines is a talent I was born with,” he said.In 1987, he finally finished his 5 robot that could walk like a man. He named it “Wu No. 1.” 6 , his experiments (实验) have not been without danger. One of his fingers was injured in 1989. And in 1999, his house was 7 by fire. In 2003, Wu and his robots were invited to perform in the Great Hall of the People in Beijing, and in 2009, his robots were on 8 along with the Chinese Shenzhou spaceships.Wu's latest dream is to invent robots 9 can help people in daily life. He will invent robots to help the disabled or look 10 children. | ||||
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