$(22)8.$ a$)$ Loads move along beams at the top chord level of the pin$-$jointed truss shown. Draw influence lines for forces in the members listed below. For each influence line, calculate and indicate the value of the influence coefficient that has the maximum absolute value. Indicate the influence coefficient as tension or compression with $"T"$ or $"C"$ respectively.

$L_1-L_2$

$M_1-L_2$

$M_1-M_2$

b$)$ Calculate the force in member $M_1-M_2$ caused by a uniformly distributed load of $6k\frac{N}{m}$ applied as a gravity load to all the beams at the top chord level of the truss.