Answer: So you need to find the area of the big circle and the little circle, if you add the diamaters they add up to 16 so we do pi*r^2 if the diameter is 16 we need the radius so we divide by 2, so we do pi*8^2, pi*64, 200.96 if we use 3.14, then we find the area of the little circle which is pi*r^2 which since the diameter is 8 we divide by 2 and get 4 so it is pi*4^2 which gets us pi*8 using 3.14 it is 25.12, now if we subtract 200.96-25.12 we get 175.84 mm