Answer
As time passes, the height of the object increases before reaching its maximum height and decreases after that.
Work Step by Step
As seen in Part A of this problem, the height of the object increases, then decreases as time passes.
At $t=0$ the height is $960$ feet. At $t=3$ the height is $1008$ feet. At $t=6$ the height is $768$ feet. At $t=9$ the height is $240$ feet.
The object reaches its highest point at 3 seconds and decreases from there. So, after reaching its maximum height, the height of the object decreases.
