Which event occurred approximately 4.6 billion years ago?

Amountain is larger than a hill, with steep sides true or false

Why the moon is not visible from earth during the new moon ?

If we represent the solar system on a scale that allows us to walk from the sun to pluto in a few minutes, then a) the planets are microscopic and the stars are millions of miles away. b) the planets are the size of basketballs and the nearest stars are a few miles away. c) the planets are marble size or smaller and the nearest stars are thousands of miles away.