What is the electron geometry (eg), molecular geometry (mg), and polarity of #SO_3#?
trigonal planar, trigonal planar & nonpolar
The best way to represent this molecule would be with each oxygen being attached to the central atom (sulfur) by a double bond. Each double bond represents two essentially parallel lines in your diagram, creating bond angles of 120 degrees between each oxygen atom according to VSEPR theory.
Because the outermost parts of the atom are identical (all O atoms), this symmetry of charge creates a non-polar character.