Area of a circle is PI x r^2
The radius of the large circle is shown as 8 m
The diameter of A is the radius of the large circle which is 8 m so the radius would be 4 m
The radius of the small circle would be 2m
Area of large circle = pi x 8^2 = 64pi = 200.96 square m
Area of middle circle = pi x 4^2 = 16pi = 50.24 square m.
Area of small circle = pi x 2^2 = 4pi = 12.56 square m.
The area of the shaded region = large - middle + small
Area = 64pi - 16pi + 4pi = p2pi square m or 200.96 -50.24 + 12.56 = 163.28 square m.