Q$1)$ Using influence lines, determine maximum positive and negative shear and maximum bending moment at joint $C$ for the loading specified.

Dead load: Uniform load of $4\frac{k}{f}t$

Live load: Uniform load of $2\mathrm{.}5\frac{k}{f}t$ and two concentrated loads $20$ kips and $10$ kips $,$ respectively, that are separated by $8$ ft $.$

Consider Design Factored Load: $1\mathrm{.}2$ DL $+1\mathrm{.}6$ LL