If an object is projected upward from ground level with an initial velocity of 144 ft per sec, then its height in feet after t seconds is given by s(t)=16t2 + 144t. Find the number of seconds it will take to reach its maximum height. What is this maximum height? The object will take second(s) to reach its maximum height. (Simplify your answer.) The maximum height reached by the object is feet. (Simplify your answer.)