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Author Question: Although we don't know for sure, changes in the strength and orientation of earth's magnetic field ... (Read 40 times)

iveyjurea

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on: Jul 16, 2018
Although we don't know for sure, changes in the strength and orientation of earth's magnetic field are most likely due to
 
  A) fluctuations in outer-core convection.
  B) variations in sea-floor spreading rates.
  C) the total number of mantle hot spots.
  D) changes in the velocity of subducting plates.

Question 2

True or False: Mantle convection occurs because upward-moving rock expands more by decompression than it contracts by cooling.
 
  Indicate whether this statement is true or false.


ricroger

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Reply #1 on: Jul 16, 2018
Answer to Question 1

Answer: A

Answer to Question 2

Answer: TRUE


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