What does the check engine code P0756 mean for a 1996 Pontiac Grand Am

[manniefresh]

GT 3.1 Engine mean? two codes came up when i got my diagnostic on my car.
one was P0756 and the other P0440.
the second one the guy told me is the gas cap.
but the other can be more serious. what exactly may be the problem?

 

[Zimgxp]

System too rich bank 1. The side of the motor with #1 cylinder. Can be caused by a dirty MAF, or a vacuum leak. A missfiring cylinder will cause this also, but then you would get a missfire code.