SolidWorks runs a simulation on a truss structure. But I am not sure what the values used for the cross-sectional areas are. How do I inspect that? I use W6x9, W8x24, and L3x2x0.25, standard profiles. But on the web one finds numbers varying by a couple of percent. Which values does SolidWorks use?

For instance, I found the volume of a bar, divided by length, and the cross-section was almost 2% lower than the value from AISC tables.