The most severe mass extinction during the past 500 million years ...

[WhattoUnderstand]

The most severe mass extinction during the past 500 million years occurred at the end of which geological period?
 
  A) Devonian
  B) Triassic
  C) Permian
  D) Cretaceous

Question 2

A satellite encircles Mars at a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity at the satellite, as compared to the acceleration of gravity on the surface of Mars, is
 
  A) one-ninth as much.
  B) zero.
  C) the same.
  D) one-third as much.
  E) one-sixteenth as much.

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Answer to Question 1

C

Answer to Question 2

E

[WhattoUnderstand]

Thank you!

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