Significant amounts of liquid water last existed on the surface of Mars during the
A) Noachian Era
B) Amazonian Era
C) Hadean Era
D) Hesperian Era
Question 2
Kepler's Third Law of planetary motion states that
A) the further a planet is from the Sun, the faster it moves in its orbit
B) an imaginary line joining the Sun and planet sweeps out equal areas in equal times
C) the further a planet is from the Sun, the slower it moves in its orbit
D) the orbits of planets are ellipses