roblem $3(\frac{15}{55}$ points$)$

the thin walled closed$-$ended cylinder shown in the figure below is subjected to an internal pressure $p=2\mathrm{.}9$MPa, a longitudinal compressive force $F,$ and a torque $T=25kN-m.$

a$)$ What is the value of $F$ if the reading of a strain gage attached to the outer surface of the cylinder and oriented along $$ was found to be $6\mathrm{.}6{10}^{-1}?$ Material: $E=190$GPa;$v=0\mathrm{.}28$

b$)$ Draw the Mohr Circles $($not on scales$),$ without calculating the principal stresses.

c$)$ If the length of the cylinder at room temperature and before loading was $2\mathrm{.}5$ m $,$ determine its final length after loading and an increase in temperature of $50C.=7\frac{{10}^{-6}}{}C$