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Ford, the second-largest car maker in the world, celebrates its 100th birthday this month.  And it is already looking forward to its next 100 years.  Ford expects to have nearly half its cars powered by fuel cells by the year 2050.  In the meantime, another large car maker in the US, General Motors, is developing the technology for cars to be powered by fuel cells.  What makes fuel cells so attractive and why are the car makers so enthusiastic about fuel cells?

Fuel cells are based on an electrochemical process.  They will change chemical energy from hydrogen and oxygen into electrical energy. 

The pollution of fuel cells is much less than that of traditional power sources.  Fuel cells produce little more than water as a by-product.  Car makers expect them to bring down CO2 production in half and so make cars more environmentally friendly.  Fuel cells are not dependent on oil supplies.  Instead, they run on hydrogen, the most common element in the universe.  And they can be refueled.  Car makers expect fuel cells to reduce the industry’s need to rely on decreasing oil supplies. 

Using fuel cells, without the traditional motor, engineers have many more prossibilities for developing cars.  A fuel cell frame can last 20 years, and car bodies could be changed to meet with drivers’ needs ? or even with the seasons ? and be replaced at will.  Some owners of the cars could change from a sports car to a family car while keeping the same fuel cell frame.  This is a much cheaper solution to buying a whole new car.  “A fuel cell car is more than just a new concept car and it’s also the start of a revolution in how cars are designed, made and used. ” said GM Chief Executive Rick Wagoner. 

Although this may sound great, fuel cells are still too expensive to produce in the USA.  For cars, they can be ten times the price of normal engines.  The current test models can cost US$1 million or more. 

試題詳情

59. By using the Internet, college students in the US can do the following except ______. 

  A. reading newspapers                 B. chatting with friends

  C. buying goods                      D. going swimming

試題詳情

58. To communicate with friends, nearly half of the college students use ______. 

  A. letters         B. e-mails           C. telephones           D. telegraph

試題詳情

57. From the fourth paragraph we can find that in the US _______. 

  A. most college students are from rich families

  B. college students can have a computer from their college

  C. cell phones will take the place of computers in college

  D. mobile phones make Internet life easy for college students

試題詳情

56. College students in the US, as this passage shows, ________. 

  A. don’t have to learn their lessons in their classroom 

  B. spend too much time visiting the Internet 

  C. lead an exciting life by visiting the Internet 

  D. waste much time visiting the Internet

試題詳情

A recent study by Harris Interactive and 360 Youth found that 93 per cent of American college students visit the Internet, and this market is expected to grow from 15. 2 million in 2003 to 16. 4 million in 2007. 

That is slow but could be the result of the already high number of college Internet users. 

About 88 per cent of American college students own a computer, and more than half have broadband(寬帶) connections.  Furthermore, 76 percent own cell phones and 36 percent use their mobile devices to visit the Internet. 

Study findings are that 42 percent go online mainly to communicate socially, and 72 percent of college students check e-mails at least once a day, with 66 percent using at least two-e-mail addresses. 

The most popular online social activity is forwarding messages to friends or family, with 37 per cent of college students saying they do so. 

The study also looked beyond the Internet surfing habits and into the buying habits of this group, and found them responsible for more than US$210 billion in sales last year alone. 

College students have learned how to spend their money, with 93 per cent saying low prices were important when shopping. 

The study also showed that 65 percent make loan payments, 41 percent of freshmen have a credit card; and 79 percent of seniors have a credit card. 

A significant number of charges on those credit cards are likely to be for entertainment and leisure expenses. 

試題詳情

54. A. he                       B. that                           C. who                       D. whoever

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53. A. point                   B. level                         C. part                       D. sign

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52. A. out                      B. over                          C. away                      D. off

試題詳情


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