Question $1$:

Do your calculation clearly and explain every step. Don't just write the answer!

For the given system, calculate the influence lines for VB$,$ M$1,$ V$2,$ M$3,$ and N$4$

$($Note: $1$ kN vertical unit force is wandering along the CB rod$)$

Use a$=2$m$,$ b$=2\mathrm{.}5$m$,$ P$=15$kN$,$ M$=10$kNm