/// <summary> Creates an arc using the 3rd ArcGeometry constructor. </summary>
        private void CreateArc3()
        {
            // Here the view is specified "by number".
            // It is suggested that you prefer to use the ArcGeometry constructor that takes a MCView object.
            var arc = new ArcGeometry(1, new Point3D(), 3.0, 0.0, 180.0);

            arc.Commit();
        }
        /// <summary> Creates an arc using the 4th ArcGeometry constructor. </summary>
        private void CreateArc4()
        {
            // Here the view to create the arc in is specified.
            // This is the preferred method of creating arcs that are not to be placed in the
            // current Construction Plane.
            // Get the View that this arc is to be created in.
            var view = SearchManager.GetSystemView(SystemPlaneType.Right);
            var arc  = new ArcGeometry(view, new Point3D(), -3.0, 0.0, 180.0);

            arc.Commit();
        }
        /// <summary> Creates an arc using the 2nd ArcGeometry constructor. </summary>
        private void CreateArc2()
        {
            var arc = new ArcGeometry(new Arc3D(new Point3D(), 1.0, 0.0, 180.0));

            arc.Commit();
        }
        /// <summary> Creates an arc using the 1st ArcGeometry constructor. </summary>
        private void CreateArc1()
        {
            var arc = new ArcGeometry();

            arc.Commit();
        }