$3\mathrm{.}16$ through $3\mathrm{.}25$ Determine the joint displacements,

member axial forces, and support reactions for the trusses

shown in Figs. P$3\mathrm{.}16$ through P$3\mathrm{.}25,$ using the matrix stiff$-$

ness method. Check the hand$-$calculated results by using Etabs

Fig. P$3.21$