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Author Question: Why can studies of carbon isotopes be used to detect the presence of past biological activity in ... (Read 30 times)

mydiamond

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  • Posts: 804
on: Jul 27, 2018
Why can studies of carbon isotopes be used to detect the presence of past biological activity in rocks?
 
  A) living organisms absorb only the most common carbon isotope
  B) living organisms remove all carbon from rocks
  C) living organisms absorb certain carbon isotopes more easily than others
  D) carbon isotopes are found only in living organisms

Question 2

What is the temperature of the universe (as a whole) today?
 
  A) 3K
  B) 300K
  C) 3000K
  D) The universe cannot be said to have a single temperature.


dominiqueenicolee

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

C

Answer to Question 2

A


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