Author Question: The most common stars are a. supergiants. b. giants. c. upper (more luminous) main-sequence ... (Read 105 times)

charchew

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The most common stars are
 
  a. supergiants.
  b. giants.
  c. upper (more luminous) main-sequence stars.
  d. white dwarfs.
  e. lower (less luminous) main-sequence stars.

Question 2

An achromatic lens
 
  a. is used to correct spherical aberration in reflecting telescopes.
  b. is used to correct chromatic aberration in refracting telescopes.
  c. is used to correct spherical aberration in refracting telescopes.
  d. is used to correct chromatic aberration in reflecting telescopes.
  e. contains two mirrors and focuses the light back through the primary mirror.



CharlieArnold

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Answer to Question 1

e

Answer to Question 2

b



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