1. .Why does Mercury have so many craters and the Earth so few?
2. Which body in the inner Solar System has the densest atmosphere?
3. Why is Venus's surface hotter than Mercury's?
4. What are the Venusian clouds made of?
5. .Mercury's average density is about 1.5 times larger than the Moon's even though the two bodies have similar radii. What does this suggest about Mercury's composition?