Problem $2$a$.$ Using the displacement method determine $($by hand calculation$)$:

a$.$ the nodal displacements;

b$.$ the reactions;

Input data: $E=1$;$I_z=1$;$l=1$;$F=2.$

Problem $2$a$.$

Problem $2$b$.$ For the given rigid$-$jointed framework $($verso$)$: $a.$ determine the maximum nodal displacement and its location; $b.$ plot the axial force, shear and bending moment diagrams.