Task $3.(25$ pts$)($CE $420/520)$

A pedestrian footbridge, modeled as the truss shown below, needs to support a distributed

load of $625lb\frac{f}{f}t.$ Assume all members have $E=29,000$ksi and $A=10i{n}^2$

Using matrix structural analysis approaches learned in this class, CE $420/520$:

Find the influence lines for the member force in members $BC$ and CD$.$

Using the influence lines, find the maximum tensile and compressive forces in

members $BC$ and $CD$ if the distributed load can be placed anywhere along the

bottom chord of the truss.