Find the Center of Mass of the Lamina That Occupies $D$

Multiple Choice

Find the center of mass of the lamina that occupies the region $D$ and has the given density function, if $D$ is bounded by the parabola $y = 1 - x ^ { 2 }$ and the $x$ -axis.
$\rho ( x , y ) = 4 y$

A) $( 8,4 )$
B) $( 4,46.44 )$
C) $( 0,0.57 )$
D) $( 12,0.57 )$
E) None of these