1)
The quarter reaches the maximum height at the vertex of the parabola.
Looking at the vertex form, we have that the vertex is (3, 256), so the time the quarter takes to reach the maximum height is the x-coordinate of the vertex, that is, 3 seconds.
2)
The quarter hits the water when the distance is equal 0, so using the factored form, we have:
[tex]\begin{gathered} -16(t-7)(t+1)=0 \\ (t-7)(t+1)=0 \\ t=7\text{ or }t=-1 \end{gathered}[/tex]So the quarter takes 7 seconds to hit the water.