A truss structure shown below is subjected to a horizontal force, $P,$ at joint $A.$ The truss is pinsupported at joint I and $J,$ and the reaction forces $,$ and $($:$J_y\}$ have been calculated and presented in the actual direction in the Figure below. Note that there is no pin connection $($no joint$)$ in the intersection point of member $BG$ and $FC.$

a$.$ Using the method of joints $($M$.$O$.$J$.),$ calculate the member forces IE and IF

b$.$ Using the method of sections $($M$.$O$.$S$.),$ calculate the member force $FC.$

Note: members $AB,CD,EF,$ and $GH$ are horizontal; members $AE,EI,DH$ and $HJ$ are vertical