QUESTION $2[25$ Marks$]$

Calculate the support moments in the continuous beam ABC $($see Fig$\mathrm{.}2)$ having constant flexural rigidity $EI$ throughout, due to vertical settlement of the support $B$ by $5$ mm $.$ Assume $E=200$GPa and $I=4{10}^{-4}{m}^4$ Also plot quantitative elastic curve.