Final answer:
When the bottom of the ladder is 6 ft from the wall, the rate of change of the angle between the ladder and the ground is zero.
Step-by-step explanation:
The given question is about finding the angle's rate of change when the bottom of the ladder is 6 ft from the wall. To solve this, we need to use trigonometry. Let's call the angle between the ladder and the ground y. We know that the distance of the bottom of the ladder from the wall is constant at 6 ft, so the rate of change of this distance is zero. Using the properties of right triangles, we can determine that the rate of change of the angle y is zero.