An equal tangent parabolic vertical sag curve is to be placed between two successive design formation grades of -3.5% and +4.5% which intersect at a chainage of 600m at a Reduced Level of 35.5m. The length of the curve is 200 m. Calculate the road design levels at 20m intervals for each of the chainages including the lowest point (RL and chainage) of the vertical curve.