The launching velocity of a missile is 20.0 m/s, and it is shot at 53º above the horizontal. which of the velocity components (neglecting air resistance) remains constant throughout the flight? horizontal ? or vertical ?

Abird flies directly overhead from where you stand at an altitude of 300.0 m and at a speed horizontal to the ground of 20.0 m/s. the bird has a mass of 2.0 kg. the radius vector to the bird makes an angle \thetaθ with respect to the ground. the radius vector to the bird and its momentum vector lie in the xyxy-plane. what is the bird’s angular momentum about the point where you are standing?