Since the launching velocity is at an angle, the launching velocity has a horizontal component and a vertical component. We can use trigonometry to find the vertical component of the velocity. Let (vy) be the vertical component of the velocity.
(vy) = v sin(theta)
(vy) = (20.0 m/s) sin(53°)
(vy) = (20.0 m/s) (0.7986)
(vy) = 16.0 m/s
The vertical component of the velocity at launch is 16.0 m/s