| − | The angle of reflection equals the angle of incidence.<ref>Wile, Dr. Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000</ref> | + | The angle of reflection equals the angle of incidence.<ref>Wile, Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000.</ref> |