1. The problem statement, all variables and given/known data A projectile is launched with a speed of 40 m/s at an angle of 60 degrees above the horizontal. Use conservation of energy to find the maximum height reached by the projectile during its flight. 2. Relevant equations KEi+PEi=KEf+PEf 3. The attempt at a solution i am not sure where vf would come from. Would it be just Vi*cos(60)? I am not sure why that makes sense. Does Vix=Vf?...and why?