a)When does the ball reach its peak?
b)How high is the ball at its peak?
c)When does the ball hit the ground?
d)How fast is it going when it hits the ground?
e)Verify and explain why the ball's acceleration is always -16 ft/sec/sec
a)Take the first derivitive (gives you the equation for speed by time) and solve it for zero . That's the amount of time it takes for the ball to quit moving.
b)Plug in your answer for a into your original equation.
c)twice your answer for a.
d)Plug in the time from c into the first derivitive equation you found in a
e)The acceleration of gravity is 16 ft/sec^2. Since your equation gives height, it's -16 ft/sec^2. I'm not sure how your teacher wants you to verify it.