An upgrade g1% is followed by a downgrade g2%. The equation of the parabolic curve of length L to be introduced, is given by

• A. <img src="/_files/images/civil-engineering/highway-engineering/33-16-117-1.png">
• B. <img src="/_files/images/civil-engineering/highway-engineering/33-16-117-2.png">
• C. <img src="/_files/images/civil-engineering/highway-engineering/33-16-117-3.png">
• D. <img src="/_files/images/civil-engineering/highway-engineering/33-16-117-4.png">