Solve the Problem $x ^ { 2 } + y ^ { 2 } = 4$

Multiple Choice

Solve the problem.
-Find the centroid of the region cut from the fourth quadrant by the circle $x ^ { 2 } + y ^ { 2 } = 4$ .

A) $\bar { x } = \frac { 2 } { 3 \pi } , \bar { y } = - \frac { 2 } { 3 \pi }$
B) $\bar { x } = - \frac { 3 \pi } { 8 } , \bar { y } = \frac { 3 \pi } { 8 }$
C) $\bar { x } = \frac { 8 } { 3 \pi } , \bar { y } = - \frac { 8 } { 3 \pi }$
D) $\bar { x } = \frac { 3 \pi } { 8 } , \bar { y } = - \frac { 3 \pi } { 8 }$