Where is the green sector?
I will assume that the central angle is pi/6 and that the radius is 10 in.
The area of the whole circle is pi*100 units^2.
The green sector has an area of
pi/6
-------- times the area of the entire circle = (1/12) of pi*100 units^2.
2pi
This comes to pi*(100 units^2)
------------------------ = (25/3) pi units^2. That's C.
12