Question 939425
The outer radius is x+2.


Volume is difference of two cylinders.


{{{3*pi*(x+2)^2-3*pi*x}}}
{{{3pi((x+3)^2-x^2)}}}
{{{3pi(x^2+6x+9-x^2)}}}
{{{3pi(6x+9)}}}
{{{highlight(18*pi*x+27)}}}