A Fireworks Shell Is Shot Straight Up with an Initial $s = 152 t - 16 t ^ { 2 }$

Essay

A fireworks shell is shot straight up with an initial velocity of 152 feet per second. Its height s feet after t seconds is given by the equation $s = 152 t - 16 t ^ { 2 }$ . If the shell is designed to explode when it reaches its maximum height, how long after being fired, and at what height, will the fireworks appear in the sky?
Please give the first answer to two decimal places and the second answer as the whole number. t = __________ sec s = __________ ft