<PRE><B>Question 1164953</B>
A projectile is launched from ground level with an initial velocity of V0 feet per second. Neglecting air​ resistance, its height in feet t seconds after launch is given by s= -16t^2 + V0t . 
-----
Find the​ time(s) that the projectile will​ (a) reach a height of 96 ft
s = h(t) = -16t^2 + 112t
-16t^2 + 112t = 96
Solve for t
2 times, ascending and descending.
----------
 and​ (b) return to the ground when V0= 112 feet per second.
------------------
-16t^2 + 112t = 0
Solve for t.
PS  t = 0 at launch</PRE>