题干

某九年级同学家住5楼.一天,他提着装有30个鸡蛋的塑料袋从1楼走到家里在此过程中,下列估算不合理的是(  )

A:他提鸡蛋的力做的功约为200J

B:他提鸡蛋的力做功的功率约为3W

C:他爬楼做的功约为6×103J

D:他爬楼做功的功率约为1×103W

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答案(点此获取答案解析)

D

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完形填空

    Jay Ruckelshaus won a full scholarship to Duke University. Then, just weeks before he was 1 to arrive on campus, he broke his neck in an accident.

    At the Shepherd Center, Jay had eight hours of exercise a day,2 his muscles and working on his 3. “Before, was 4 setting goals and achieving them. But this was not what you could achieve.”

    5the breakthrough came: He was able to 6 on his own, eat, and use an iPad. “The iPad was great, ”he said, “That gave me 7 to the world.” To stretch his mind further, he 8 for courses online.

    Most people, he said,9 he would change his plans to study after his accident. But throughout his 10 his place at Duke University was what kept him going. For Jay, there was never any 11 he would go to Duke. “There was also no doubt from the university, which was wonderful, and wouldn't have been the 12 at some other schools.

    Finally getting into Duke a year later than planned,13being in a wheelchair, he was 14 to have a fun college life. He needed 15, but soon made great friends. In 16 studying for a degree and sitting co-editing a journal, he was able to hang out with friends.

    Also, he thought of other wheelchair users and decided to help them. “I 17I was having an amazing time and meeting amazing people,” he said. The feeling was almost 18. Therefore, he started a charity called Ramp Less Traveled to spread the 19 that college is 20 for students with spinal cord (脊髓) injuries.