As time passes when the object is thrown up, it reaches a maximum height and then goes back down.
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 576 feet. At $t=2$ the height is 672 feet. At $t=4$ the height is 640 feet. At $t=6$ the height is 480 feet. The object reaches its highest point at 2 seconds and decreases from there. So, after reaching its maximum height, the height of the object decreases.