For problem $2,$

$(4$ pts$)$ A truss structure shown below is pin supported at joint A and roller supported at joint $L.$ The reactions of these supports due to the applied forces at joints $C,H,$I, and $J$ have been calculated and presented in the figure below.

a$.$ Identify all zero$-$force members on the truss by writing down the members' label.

b$.$ Using the Method of Joints $($M$.$O$.$J$.),$ calculate the member forces $AB,AH,BC.$

c$.$ Using the Method of Sections $($M$.$O$.$S$.),$ calculate the member forces $EF,EJ,$ and $IJ$