The area of the load of cylinder can be given as,
[tex]A=\pi(d^2_2-d^2_1)[/tex]Plug in the known values,
[tex]\begin{gathered} A=(3.14)((4in)^2-(2in)^2) \\ =(3.14)(16in^2-4in^2) \\ =(3.14)(12in^2) \\ =37.68in^2 \end{gathered}[/tex]The retraction force acting on the cylinder is,
[tex]F=PA[/tex]Substitute the known values,
[tex]\begin{gathered} F=(1500psi)(37.68in^2)(\frac{1\text{ lbf}}{1p\text{ s}in^2}) \\ =56520\text{ lbf} \end{gathered}[/tex]Thus, the force exerted on the cylinder is 56520 lbf.