The formula for the area of a circle is A = πr^2, where r is the radius of the circle.
Since the diameter of the circle is given as 28 centimeters, we can find the radius by dividing 28 by 2:
radius = diameter/2 = 28/2 = 14 centimeters
Using π = 3.14, we can estimate the area of the circle as:
A = πr^2 = 3.14 x 14^2 = 3.14 x 196 = 615.44 square centimeters
Therefore, an estimate of the area of the circle is 615.44 square centimeters.