One of the differences between CD-RWs and CD-ROMs is

试卷相关题目

• 1E-mail is mentioned in the third paragraph to show

  A.the variety of digital communications

  B.the development of new technologies

  C.the usefulness of digital codes

  D.the relationship between communication and technology

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• 2Music is recorded onto CDs as

  A.laser beams

  B.digital codes

  C.musical notes

  D.special sounds

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• 3It can be found from the last paragraph that infrasonic waves

  A.are harmless to people's health

  B.exist in people's internal organs

  C.can be used as deadly weapons

  D.can improve eyesight

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• 4An ultrasonic sound

  A.is very loud

  B.does harm to people's health

  C.cannot be heard by people

  D.is produced by the hero in movies

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• 5It is true that the sound

  A.of nature is the most beautiful

  B.over 80 decibels is harmful to people

  C.of high intensity benefits animals

  D.in movies is pleasing to the ear

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• 6CDs can last a long time if

  A.they are seldom used

  B.they play well and sound fine

  C.their users take good care of them

  D.they are developed with new technology

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• 7It can be inferred from the passage that

  A.CD-ROMs are more expensive than other CDs

  B.new technology for music recording is being developed

  C.the author likes listening to music

  D.flppy disks are no longer in use

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