If a Ball Is Thrown Directly Upward with a Velocity $y = 48 t - 16 t ^ { 2 }$

Multiple Choice

If a ball is thrown directly upward with a velocity of 48 ft/s, its height (in feet) after t seconds is given
By $y = 48 t - 16 t ^ { 2 }$
) What is the maximum height attained by the ball?

A) $48 \mathrm { ft }$
B) $16 \mathrm { ft }$
C) $32 \mathrm { ft }$
D) $54 \mathrm { ft }$
E) none of these