I.11.21 Triple integrals

condition: Find the mass of a body of density \( \rho \) bounded by these surfaces. Parameter a is positive. \[ \begin{array}{l} x^{2}+y^{2}+z^{2}=a^{2}, \quad x^{2}+y^{2}=z^{2}, \\ \rho=\sqrt{x^{2}+y^{2}+z^{2}} . \end{array}\]