O.T. Query: back of U.S. one-dollar bill

[Gerald Cohen]

   The back of a U.S. dollar bill has two circles; I never paid much
attention to the contents of the one on the left, but today I was
asked about them:

1) What does the pyramid symbolize?
2) What is the symbolism of the eye in the triangle (with the
triangle seemingly being the top of the pyramid but for some reason
detached from it)?
3) What exactly does the Latin "Annuit Coeptis" mean?
4) What exactly is the meaning of the Latin "Novus Ordo Seclorum"? It
looks like "New Order of the Ages," but what exactly does this mean?

    I'd be grateful for any clarification.

Gerald Cohen