That would be called an Apatheist.
There's so many different terms that people have created, it's silly.
Anyways my answers:
Age: 21, atheist
1. Depends on your definition of 'God'
If you mean a God as defined in the Christian bible, with every quality listed, and having performed every act claimed, then I can say I am entirely sure this god does not exist. If you mean in an extremely generic sense, perhaps a deistic god who simply created the universe then stepped back, there is no reason for his existence or nonexistence to be known, and no reason for said god to care. There isn't any evidence to justify a belief.
2. To me, faith is the belief in something,
always with a lack of supporting evidence, and
usually in the presence of contradicting evidence. It's belief in something because you
want it to be true. A god always watching over you, like a strong father figure, protecting you, and giving you something to look for after death, really is a nice thing to want to believe to be true.
3. It's just a bunch of things I've discovered through my life. Very general things that are often cited, like this biblical claim being contradicted by science backed up by evidence, that biblical claim just being entirely silly, down to specific things like "how could a save god hate someone for having a quality that he created them to have?"
4. All sorts of things in life that are there to be experienced