UPSC Civil Service Exam Questions - Engineering

Q1:

If the gradient of a ground is -3%, that of another ground intersecting with the former is 5%, and the horizontal length of the vertical curve to be drawn is 600 m, then the vertical offset 'e' from the vertex of the vertical curve to the mid-point of the curve will be

A 1.5 m

B 6 m

C 15 m

D 75 m

ANS:B - 6 m

Please give an explanation of the answer.