Problem

6. (a) $\displaystyle\iint_D y\,dA = \underline{\quad(15)\quad}$, where $D$ is the region in the first quadrant that lies between the circles $x^2+y^2=4$ and $(x-1)^2+y^2=1$.

(b) The volume of the solid $R$ lying below the plane $z=3-2y$ and above the paraboloid $z=x^2+y^2$ is $\underline{\quad(16)\quad}$.