What is the difference between a gibbous moon and a crescent moon? (Select all that apply.)

A crescent moon has less than one half of its observed surface illuminated.
A gibbous moon has less than one half of its observed surface illuminated.
A crescent moon has more than one half of its observed surface illuminated.
A gibbous moon's observed surface is completely dark.
A gibbous moon has more than one half of its observed surface illuminated.
A crescent moon's observed surface is completely illuminated.
A crescent moon's observed surface is completely dark.
A gibbous moon's observed surface is completely illuminated

- A crescent moon has less than one half of its observed surface illuminated.

- A gibbous moon has more than one half of its observed surface illuminated.