Two identical circles intersect such that their centers and the points at which they intersect form a square of side 0.5 cm. What is the area of the region where the two circles intersect?  Select
A) 2pi - 4  B) pi -2  C) pi/2 - 1  D) pi/4 - 0.5  E) pi/8 - 0.25
Drawing a diagram, we see that the radius of the circle equals the side of the square.   The area of intersection is: pi*r^2/4 - (r^2-pi*r^2/4) = pi*r^2/2 - r^2 = pi/8 - 0.25   The answer is pi/8 - 0.25.
<result>E</result>
Two identical circles intersect such that their centers and the points at which they intersect form a square of side 0.5 cm. What is the area of the region where the two circles intersect?