Hi, I don't think I can say my age, but i'm in my mid teens (the median of 13 & 19, you do the math

) and I currently stand about 5'7 to 5'8; but my goal is 6 ft. or taller because I want to pursue a career in basketball (we all can have dreams... don't we?). I'm African American if that helps, and according to my growth chart & my self awareness, I think i've fallen from the 65-70th percentile to the 50th soon after puberty. Is it possible if I can rise again?
I asked my mom about various heights from both sides of my family, and it turns out that while my mom's side is pretty well rounded (some tall, short, and average heights in there), my dad's side seems to lean towards the tall side. I guess this lifts a little off my mind, but i've read (and been told) that most people stop growing at the age of 18. Contrary to that belief, i've also seen that people can keep growing until the age of 24 or so. So what I think i'm asking is...
1. Is there a definite age that people stop growing?
2. Is it possible to grow 5 inches in 2 years (if the age that people stop growing IS indeed 18)
3. Is there a chance I can reach 6 feet?
4. Any NATURAL ways to make sure I reach my maximum height potential?
Thanks for reading, and please don't mind if I post some more questions as they pop in to my mind.
Thanks again, please reply.