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Author Question: Adding a secondary concave lens of carefully chosen different glass to the primary lens on a ... (Read 65 times)

j.rubin

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  • Posts: 557
on: Jul 27, 2018
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

  • Sr. Member
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  • Posts: 335
Reply #1 on: Jul 27, 2018
Answer to Question 1

A

Answer to Question 2

TRUE


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