The word horsepower(马力) was first used two hundred years ago. (200年前“马力”这个词首The word horsepower(马力) was first used two hundred years ago. (200年前“马力”这个词首次使用。) James Watthad made the first widely used steam(蒸气)engine. He had no way of tllingpeople exactly how powerful it was, for at that time there were no units for measuring (测量)power.Watt decided to find out how much work one strong horse could do in one minute. He called thatunit one horsepower. With this unit he could measure the work his steam engine could do.He discovered that a horse could lift a 3,300-pound weight 10 feet into the air in one minute.Hisengine 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 horsepowerengine.1.The passagesays that Watt made the first widely used steam engine.A.TB.F2.Watt made up a unit of measurement based on the strength of a horse.A.TB.F3.Watt wanted to find a way to lift a 3300-pound weight.A.TB.F4.One horsepower would equal the weight a horse could lift.A.TB.F5.The title of the passageis "How the Term Horsepower Came into Being".A.TB.F

第1题

After Man has dreamed about flying for a long time. Michael Moshier is a dreamer. He inven

ted the Solo Trek.

The Solo Trek had a 120 horsepower engine with twin fans. Only one person flies. As you fly above the roofs, you lean a little forward. You can see everything under you. You are flying like Superman.

Michael Moshier looked at the jet belt and the rocket belt that was developed 20, 30 years ago. Nothing ever came from them. People still can't fly.

Inventors have tried to make it easy for people to fly. Paul Moiler has been working on his flying car for 30 years. He now says it is ready for tests. It would take off and land vertically, go 600 miles an hour, and deliver 20 miles to the gallon. A computer would do the actual flying. He says it could be sold next year for about a million dollars.

NASA is working with Moshier to help develop his flying machine. The first users are likely to be military.

It's been 50-years since Robert Fulton invented his airphibian, a flying car. It flew, and is now in the Smithsonian Museum.

Getting dreams to fly is never easy.

The Solo Flyer is able to lift off the ground by using ______.

A．a solar powered engine

B．engine-powered twin fans

C．large flapping wings

D．rotating blades

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第2题

The energy which the sun radiates goes in every direction, and only a minute part of it fa

lls on the earth. Even so, it represents power of about 5,000,000 horsepower (马力)per square mile per day; the sun gives us as much energy every minute as mankind utilizes in a year. At present, we use this energy in directly, and it is our final source of power. Coal represents the chemical action of the sun on green plants thousands of years ago. Water power results from the rain formed by vapor which comes from the evaporation of power. Coal represents the rain formed by vapor which comes from the evaporation of water under the sunshine. Even windmills operate because of air currents set in motion by the different heating affects of the sun in different places. Some day, through chemistry or some type of solar engine, we shall harness this great source of energy more directly. Already a scientist has worked out an engine, surprisingly efficient, in with the sun' s rays are concentrated through mirrors on a tube of water to create steam.

How much energy given off by the sun reaches the earth？

A．100 % but indirectly

B．5 %

C．0.5

D．only a very tiny amount

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第3题

The word “provisional” means______.

A.temporary

B.proposal

C.powerful

D.revolutionary