1. A man slides along a long water slide and then being launched into the air to land in a water pool. Landing sites and includes a superimposed coordinate system with its origin conveniently located at the launch site. The horizontal flight distance as D = 20.0 m, the flight time as t = 2.50 s, and the launch angle as ? = 40.0°.
a. Find the magnitude of the velocity at launch.
b. Find the magnitude of the velocity at landing.