A horizontal curve on a two-lane highway is designed with a 818.51ft radius, 12ft lane, superelevation 6.4%, and a 50mph design speed. Deflection angle is 90 degree. The maximum relative gradient is 0.50. The superelevation is achieved through rotated around the centerline. Determine the spiral curve length to satisfy all requirements (roundup to nearest 10ft).
(Optional and bonus 10pts) The TS station is 10+53.21, determine CS, SC and TS stations