To determine the length of time that will pass before the plane will land, set this altitude function = to 0 and solve for t: This assumes that "land" is at sea level.
(5 m/sec)t = 8500 m
t = (8500 m) / (5 m/sec) = 1700 sec, or 28.33 min (since 60 sec = 1 min)
