Pls help me :( A model rocket is launched from a platform and its height h metres is given as a function of
the elapsed time t seconds by 2 htt =− + + 4 9 180 2 . . Using a graphing calculator determine:
a) the maximum height of the rocket
b) the time required for the rocket to reach its maximum height
c) the time required for the rocket to reach the ground

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)