Answer:
h = -0.0166t^2 + 30.
Step-by-step explanation:
The graph of the flight is a parabola which opens down and is symmetrical about the y axis, passes through the x axis at -42.5 and 42.5 and has a vertex at (0, 30).
So we have -a(t^2) + 30 = 0 where t is the time
(42.5)^2 * -a = -30 (42.5 as its 1/2 * 85).
a = 30/2806.25
= 0.01661
So the equation is height h = -0.0166t^2 + 30
