To find the diameter \( d \) of a circle with a given circumference \( C \), you can use the formula:
\[ d = \frac{C}{\pi} \]
Given that \( C = 125.6 \) feet and using \( \pi \approx 3.14 \):
\[ d = \frac{125.6}{3.14} \]
Now, perform the division:
\[ d \approx 40.06 \text{ feet} \]
So, the diameter \( d \) of the circle is approximately 40.06 feet.