HELP! I have 3 algebra based physics problems I need help starting. I dont want answers, just help picking formulas to use and such. 1) a fighter plane has an air speed of 200 m/s. A projectile is launched at 50 m/s in a forward direction, with a 30 degree angle relative to the plane's motion. What is the speed of the projectile with respect to a stationar observer on the ground? 2) An anti-tank weapon fires a 3kg rocket which aquires a speed of 50m/s after traveling 90cm down a launching tube. What force is acted on it? 3) A 10 kg block rests on a table. The coefficient of static friction os 0.50. If someone pushes down on the block with a force of 48N what is the maximum horizontal pull that will NOT move the block? Any help would be greatly appreciated! Thanks.