Which statement best describes the surface of Europa?
a. dark and dirty ice, heavily pocked with craters
b. old and dark on some portion, but cratered with a young bright grooved terrain
c. icy crust free of craters with a liquid water ocean beneath
d. covered in active sulfur-based volcanoes
e. mostly water ice mixed with methane
Question 2
Which best describes the surface of Callisto?
a. dark and dirty ice, heavily pocked with craters
b. old and dark on some portion, but cratered with a young bright grooved terrain
c. icy crust free of craters with a liquid water ocean beneath
d. covered in active sulfur-based volcanoes
e. mostly water ice mixed with methane