Question

Clear your results and remove the air resistance. Collect data to figure out how the angle must be changed to hit the bull's-eye as the initial speed changes.

Initial speed = 14 m/s

Angle = ___?___

I have to answer the above question using http://phet.colorado.edu/sims/projectile-motion/projectile-motion_en.html But I do not understand how to write out the answer Angle=___?____