Problem $2(20$ pts$)$: For the truss shown below, determine the

horizontal displacement at Node C by both SAP$2000$ and hand calculation. The cross$-$sectional area and Young's modulus of all members are constants as A$=300$mm$^(2)$ and E$=200$GPa,

solving by hand, I got $40$ mm of horizontal displacement, which seems way too big. Can someone do it so I can see where I messed up no way $40$ is right