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Author Question: How did oxygen (O2 ) get into Earth's atmosphere? A) It was captured from the solar nebula. B) ... (Read 91 times)

rachel9

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on: Jul 27, 2018
How did oxygen (O2 ) get into Earth's atmosphere?
 
  A) It was captured from the solar nebula.
  B) It was outgassed from volcanoes.
  C) It came from chemical reactions with surface rocks.
  D) It was released by life through the process of photosynthesis.

Question 2

An intermediately wound barred spiral galaxy would be
 
  A) BS2.
  B) BSE.5.
  C) SBb.
  D) S2B.
  E) SIrr.


amanda_14

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

D

Answer to Question 2

C


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rachel9

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Reply #2 on: Jul 27, 2018
TY


amanda_14

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Reply #3 on: Jul 27, 2018
You're welcome


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