A spherical solid, centered at the origin, has radius 9 and mass density $\delta(x,y,z)=15 -\left(x^2+y^2+z^2\right)$. Find its mass.

$\displaystyle\int \!\! \int \!\!\int \, \delta(x,y,z)\, dV =$

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$\displaystyle\int$

$\displaystyle\int$

$\hspace{5pt}d\rho d\theta\ d\phi =$

For your answers $\theta$ = theta, $\rho$ = rho, $\phi$ = phi.