For the first one, older books and stuff like that say there are 7, but more recently some geologists think they're 8. So, for right now, it's false.
True, Ancient Greece was a model for the U.S. government, but the founders left a few things out. But there are many facets of Greek democracy that didn't catch on.
True.
So you're answers are: True, True, False
Explanation:
It proved to be the key to deciphering Egyptian hieroglyphs mensing it opened an opportunity for the first time into ancient Egyptian history