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Author Question: How do geologists know that the magnetic field of Earth has changed constantly over time? A) by ... (Read 78 times)

mydiamond

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on: Jul 16, 2018
How do geologists know that the magnetic field of Earth has changed constantly over time?
 
  A) by the direction of historical lava flows, which they have been able to date with radioactive dating methods
  B) by crystals that have formed in metamorphic rocks
  C) by records kept in magnetic rock-forming minerals
  D) by analyzing and extrapolating records kept by scientists since the 1600s

Question 2

Why is the lower mantle thicker than the upper mantle?
 
  What will be an ideal response?


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cuttiesgirl16

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

Answer: C

Answer to Question 2

Answer: more pressure


mydiamond

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Reply 2 on: Jul 16, 2018
Great answer, keep it coming :)

frankwu0507

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Reply 3 on: Yesterday
Excellent

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