Given:
Given that the radius of circle is 3 miles.
We need to determine the area of the circle.
Area of the circle:
The area of the circle can be determined using the formula,

where r is the radius of the circle.
Substituting π = 3.14 and r = 3 in the above formula, we get;

Simplifying, we get;

Multiplying, we have;

Rounding off to the nearest tenth, we get;

Thus, the area of the circle is 28.3 square miles.