## College Physics (4th Edition)

We can find an equation for the vertical position as a function of time: $y = v_{0y}~t+\frac{1}{2}a_y~t^2$ $y = -4.9~t^2+v_{0y}~t$ This is the equation of a parabola that is concave down. Note that $y = 0$ at time $t = 0$. The correct answer is: (d)