# Length of Parabolic Sag Curve with Given Change in Grade Per Station

**Problem**

A grade of -5% is followed by a grade of 1%, the grades intersecting at the vertex (Sta. 10 + 060). The change of grade is restricted to 0.4% in 20 m. Compute the length of the vertical parabolic sag curve in meters.

A. 360 m | C. 300 m |

B. 320 m | D. 340 m |