The square has sides of 4 inches, because 4*4=16. The radius of the circle is 4/√π. Because of the 45/45/90 triangle rules, we know that the diagonal of the square is 4√2. Half of 4√2 is 2√2. This half-diagonal overlaps with a radius of the circle; the radius is smaller because the corner sticks out. The answer is 2√2– (4/√π). Use a calculator to find √2 and √π in 'rational' numbers, and solve it from there. For part B, you know that half the side of the circle is 2, and a radius would overlap with that. So that answer is 4/√π – 2. After you solve out those answers, you'll have part C