The position of a softball tossed vertically
upward is described by the equation

y = c_1 t − c_2t^2

where y is in meters, t in seconds, c_1 =

7.13 m/s, and c_2 = 4.49 m/s^2

Find the ball’s initial speed v_0 at t_0 = 0 s.

Answer in units of m/s.