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Author Question: The _____ is a geologically brief period about 540 million years ago during which fossil evidence ... (Read 61 times)

jon_i

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on: Jul 27, 2018
The _____ is a geologically brief period about 540 million years ago during which fossil evidence indicates Earth life became complex and diverse.
 
  A) Cambrian explosion
  B) Paleozoic era
  C) Renaissance
  D) Ordovician

Question 2

Which of the following does N represent in the Drake equation, Nc = N  fp  nHZ  fL  fI  fs?
 
  A) The average number of planets in a solar system
  B) The fraction of stars that have planets
  C) The number of stars in our galaxy
  D) The fraction of suitable planets on which life begins


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jomama

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

A

Answer to Question 2

C


jon_i

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Reply 2 on: Jul 27, 2018
:D TYSM

marict

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Reply 3 on: Yesterday
Excellent

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