Answer: 7.6 feet.
Explanation:
1. Based on the information given in the problem, you can draw a right triangle as the one shown in the figure attached, where x is the distance between the foot of the stop sign and the stake.
2. Then, you can calculate x as following:

Where:

Substitute values and solve for x:

3. To the nearest tenth of a foot, the distance is: 7.6 feet.