The grooved terrain found on Ganymede is believed to be a. ...

[JMatthes]

The grooved terrain found on Ganymede is believed to be
 
  a. flow channels for liquid water.
  b. flow channels for liquid methane.
  c. a system of faults in the crust.
  d. the peaks of water waves in a large ocean.
  e. caused by meteor impacts with the surface of Ganymede.

Question 2

The Roche limit is the
 
  a. distance from the Sun within which a planet cannot retain an atmosphere.
  b. minimum mass of an object in the solar system that would be classified as a planet.
  c. maximum separation distance between the Sun and a given planet.
  d. distance from Earth at which we lose radio communication with a satellite.
  e. distance from a planet within which a planet cannot hold itself together.

[welcom1000]

Answer to Question 1

c

Answer to Question 2

e

[JMatthes]

Excellent

[ecabral0]

Great answer, keep it coming