how do u build a bottle rocket?

Question

it cant be higher than 76 cm long. it needs to have fins with a with of at max 10 cm. it also needs a ballast and a nose piece. in other words, wut do i use to fill the ballast, to make the nose peice, and wut shape fins. plz help me!

Answer 1

http://teacherlink.ed.usu.edu/tlnasa/units/Rockets/18BottleRocket.pdf