opengameart in paid game

opengameart in paid game

Hello, i am new to developing games hence i am not good at art. i have downloaded some art for my game from opengameart and there were some licenses to the arts such as :

CC-BY 4.0/CC-BY 3.0/GPL 3.0/GPL 2.0/OGA-BY 3.0/CC by SA-3.0
i will be making some changes to the art.

here are some things i want to clarify before i use it in making my game:

1)i wanted to ask that can i use such licensed art in my game which i intend to make it a paid game provided that i credit/attribute the art makers properly as they have mentioned for free?

2)another thing i want to ask is there wont be any legal trouble right?

3)will i have to pay the artists?