What percentage is the maximum range of a projectile if the initial velocity is increased by 10%?

A projectile fired from the ground has a velocity at a height of 9.10 m. Find:

(a) the initial velocity 

(b) the maximum height 

A projectile is launched with an initial velocity of 60.0 m/s at an angle of 30.0 above the horizontal. What is the maximum height reached by the projectile?

A projectile is launched from ground level with an initial speed of 48.2 m/s. Find the launch angle (the angle the initial velocity vector is above the horizontal) such that the maximum height of the projectile is equal to its horizontal range. (Ignore any effects due to air resistance.)