How did oxygen (O2 ) get into Earth's atmosphere? A) It was captured from the solar nebula. B) ...

Author Question: How did oxygen (O2 ) get into Earth's atmosphere? A) It was captured from the solar nebula. B) ... (Read 74 times)

rachel9

Sr. Member
Posts: 495

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

Sr. Member
Posts: 342

Reply #1 on: Jul 27, 2018

Answer to Question 1

D

Answer to Question 2

C

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rachel9

Sr. Member
Posts: 495

Reply #2 on: Jul 27, 2018

amanda_14

Sr. Member
Posts: 342

Reply #3 on: Jul 27, 2018

You're welcome

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