Step-by-step explanation
We need to apply the equation for a circumference in order to get the needed value, as shown as follows:

As we don't know the radius, but just the area, we need to isolate it from the surface equation:

Substituting terms:

Isolating the radius:

Applying the square root to both sides:

Plugging in the radius into the equation of circumference:

Multiplying terms:

In conclusion, the Circumference is equal to 69.06 feet.