SOLUTION: Mitch tossed an apple to Kathy, who was on a balcony 40 feet above him, with an initial speed of 56 feet/second. Kathy missed the apple on its way up, but caught it on its way down

As you know  (or must know),  the equation for the height above the ground for this case is

    h(t) = -16t^2 + 56t.


The maximum height is reached when this quadratic function gets its maximum, i.e.  at  t =  =  =  seconds, 
and is equal to  

     =  = 49 feet.


To find the zeroes, solve the equation

   h(t) = 0,  which is the same as  -16t^2 + 56t = 0,

                                     = 0,


so the zeroes are these values of t:  t= 0 seconds (start) and  t=  =  seconds (finish).