5. Add a horizontal line, representing the total energy of the system, to the plot. (The line should be above the horizontal. axis ).. Label the turning points on the plot Are the turning points symmetric about the natural length. or the mass. equilibrium? 6: Does the choice of coordinate system matter ? show that the y-coordinate of Umin is independent of coordinate system .. ( For example, you could let y= 0 correspond w / mass. equilibrium, rather than natural length, & repeat steps. 1 -3. above. )