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Author Question: The aurora borealis (northern lights) are caused by a. sunlight reflecting from polar ice b. ... (Read 108 times)

APUS57

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on: Jul 28, 2018
The aurora borealis (northern lights) are caused by
 a. sunlight reflecting from polar ice
  b. emissions from atoms and molecules in the upper atmosphere excited by electrons from the sun
  c. thunderstorms
  d. an unknown process

Question 2

Lasers are used
 a. to produce holograms
  b. in surgery
  c. to measure distances between objects accurately
  d. in DVD and compact disc players
  e. all of the above


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canderson530

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Reply #1 on: Jul 28, 2018
Answer to Question 1

B

Answer to Question 2

E


APUS57

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Reply #2 on: Jul 28, 2018
Thank you!


canderson530

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Reply #3 on: Jul 28, 2018
Always glad to help...


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