Hayden is playing with a toy airplane. The height of the airplane, in centimetres, is given by the relation h=-6t^2+43t+20, where t is the number of seconds since the
plane was launched.
a) For how long will the airplane be in the air, rounded to the nearest tenth of a
second?
b) At what time(s), rounded to the nearest tenth of a second, will the airplane reach a
height of 45 m?
c) When does the toy plane reaches the maximum height?
d) What is the maximum height?