16. A projectile is fired at time t = 0.0 s from point 0 at the edge of a cliff, with initial velocity components of Yox = 30 m/s and Voy - 100 m/s. The projectile rises, and then falls into the sea at point P. The time of flight of the projectile is 25 s. Assume air resistance is negligible. What is the magnitude of the velocity at time r=15.0s