QUESTION $4$

For the statically determinate pin$-$jointed roof truss shown in Figure $4,$ determine the following

a$)$ The support reactions.

b$)$ The magnitude and nature of the real member internal forces.

c$)$ The magnitude and nature of the virtual member forces.

d$)$ The vertical deflection of joint $D.$

Take $A=100m{m}^2$ and $E=200$GPa