题目内容：
The word horsepower was first used two hundred years ago. James Watt had made the world' s first 11__________used steam engine. He had no way of telling people 12__________ how powerful it was, for at that time there were no units for measuring power. Watt decided to 13__________ how much work one 14 __________horse could do in one minute.He called that unit one horsepower. With this unit he could measure the work his steam engine could do. He 15__________ that a horse could lift a 3,300-pound weight 10 feet into the air in one minute. His engine could lift a 3,300-pound weight 100 feet in one minute. Because his engine did ten times as much work as the horse, Watt
called it a ten horsepower engine.
__________
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