Hayden is playing with a toy airplane. The height of the airplane, in metres, is given by the relation h=-3t^2+48, where t is the number of seconds since the plane was
launched.
a) For how long will the airplane be in the air?
b) Determine the time when it reaches its maximum height? What is the maximum
height?
c) At what time(s), rounded to the nearest tenth of a second, will the airplane reach a
height of 30 m?