To calculate the circumference \( C \) of a circle, the formula is:
\[ C = 2 \pi r \]
where \( r \) is the radius. Given that the radius \( r \) is 2.5 feet and using \( \pi \approx 3.14 \):
\[ C = 2 \times 3.14 \times 2.5 \]
Calculating this:
\[ C = 6.28 \times 2.5 = 15.7 \text{ feet} \]
So, the circumference, estimated to the tenths place, is 15.7 feet.