\
Step 1 :
\Conversion from rectangular to cylindrical co-ordinates :
\
Conversion of integral from rectangular to cylindrical co-ordinates :
\
Step 2 :
\The solid is .
The density function is .
Substitute in above equation.
The density function in cylindrical co-ordinates is .
Find the z limits :
\Substitute and
in above inequality.
Find the r and limits :
is an equation of the circle with radius
.
Thus, and
.
Step 3 :
\Find the mass of the solid :
\The mass is
Substitute the corresponding values in above equation.
\
Solution :
\The mass of the solid is .