Solve the Problem. -A Person Standing Close to the Edge on Top of on Top

Multiple Choice

Solve the problem.
-A person standing close to the edge on top of a 320-foot building throws a baseball vertically upward. The quadratic function s(t) = -16t2 + 64t + 320 models the ball's height above the ground, s(t) , in feet, t seconds after it was thrown. After how many seconds does the ball reach its maximum height? Round to the nearest tenth of a second if necessary.

A) 2 seconds
B) 6.9 seconds
C) 384 seconds
D) 1.5 seconds