12. Let S be a square and R the region inside the square where the points are closer to the square's center than to its edge. Find the ratio of R to S [answer in format where a and bare integers, c and d are natural numbers]. Potential Hints: Definitely easiest to center the square at the origin. And it might be easier to use a unit square rather than a random square [this is allowed and doesn't detract from the proof]. The four boundaries of R end up all being parabolic. Find the top boundary algebraically and use reflections for the other 3. And then..