Author Question: Adding a secondary concave lens of carefully chosen different glass to the primary lens on a ... (Read 56 times)

j.rubin

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Adding a secondary concave lens of carefully chosen different glass to the primary lens on a refractor allows
 
  A) chromatic aberration to be reduced.
  B) more light to be gathered.
  C) greater magnification.
  D) X-rays to be focused.
  E) effects of atmospheric turbulence to be reduced.

Question 2

Main sequence stars are fusing hydrogen into helium in their cores.
 
  Indicate whether the statement is true or false



Li Jun

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Answer to Question 1

A

Answer to Question 2

TRUE



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