We are given the structure shown in Figure $1.$ The horizontal distance dis very small and can be taken equal to zero. We are given that $EI={10}^6$kip$-f{t}^2$ for members $AB$ and $BC.$

a$)$ Calculate the axial force of member $(1-3),$ and detect the zero$-$force truss members $($if any$).(10$ points$)$

b$)$ Calculate the reactions at point A$.(5$ points$)$

c$)$ Determine the moment diagram, $[$M$],$ for member $AB.(5$ points$)$

d$)$ Calculate the horizontal displacement at point $B,$ using the unit load method. $(10$ points$)$