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Author Question: As a star forms, the photosphere first appears: A) when the planetary nebula is expelled. B) ... (Read 59 times)

Lisaclaire

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on: Jul 27, 2018
As a star forms, the photosphere first appears:
 
  A) when the planetary nebula is expelled.
  B) when the protostar forms.
  C) when contraction slows down.
  D) when nuclear fires ignite.
  E) when the star reaches the main sequence.

Question 2

The particles which enter into chemical reactions are the atom's:
 
  A) protons.
  B) neutrons.
  C) positrons.
  D) electrons.
  E) mesons.


amandanbreshears

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Reply #1 on: Jul 27, 2018
Answer to Question 1

B

Answer to Question 2

D


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