I think that you have to find the area so you have to know the radius of the circle that is 3.9 you just divide 7.85 by 2 is equal 3.9 and then you find the area with tge formula A=
[tex]a = \pi r {}^{2} [/tex]
so you have to multiply 3.9 times 3.9 and the results is 5.21
