PROB $3$: $10$ PTS

For the structure consisting of the three truss elements as shown, determine a$)$ the thermal nodal load vector due to a $100$ F temperature increase in element I and $50$ F in element II$,$ and b$)$ the stress in elements I$\backslash$& II$.$ A$=4$ in$**2,$ thermal expansion coefficient$=1$E$-5($in$/$in$)/$F$,$ E $=30$E$6$ psi, L$=60$ in$.$

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