Find the volume of a solid that lies above the plane $\displaystyle xOy$ and is bounded by the surfaces $\displaystyle x^2+y^2+z^2=1$ and $\displaystyle x^2+y^2-z^2=0$.

Start of a solution:

We can find $\displaystyle f(x,y) = z$, i.e., $\displaystyle z = \sqrt{1-x^2-y^2}$ and $\displaystyle z = \sqrt{x^2+y^2}$.

I know that this involves multiple integrals, but my book was not very helpful and I cannot remember how to set this up.