The Mathematical connection of Spline and the quality of Surfaces

Hello,

It's known that the mathematical connection of a spline is a polynom. Is it possible to know what is the order of the spline's polynom that SolidWorks uses? Is it constant order or change from one spline sketch to another?

Also, I have heard the expression of Class A surface which refers to quality of a surface with continuity of G3 and G4. Is it something that possible to reach with SolidWorks and if yes, how?

Thanks,

Aviv

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