Convert the integral from rectangular coordinates to both cylindrical and spherical coordinates.

${\displaystyle \underset{0}{\overset{2}{}}}{\displaystyle \underset{0}{\overset{\sqrt[\phantom{2}]{4-x^2}}{}}}{\displaystyle \underset{0}{\overset{\sqrt[\phantom{2}]{16-x^2-y^2}}{}}}\sqrt[\phantom{2}]{x^2+y^2}dzdydx$

cylindrical:

spherical:

Evaluate the simplest iterated integral.