Surface of Revolution Template

LARGE POINTS are moveable. The points along the curve stay on the dashed grid. To move the dashed line, move any of the 2 points that lie on it. Click on any point lying on the dashed line and then drag it to move it within the plane containing the grid.   Click on this point again and then drag it up or down to move it off the plane containing the grid.   Move the point with the arrows to spin the curve about the dashed line to form the surface of revolution.