A sewer is laid from a manhole to a manhole , 250 m away along a gradient of 1 in 125. If the reduced level of the invert at is 205.75 m and the height of the boning rod is 3 m, the reduced level of the sight rail at , is

Surveying and leveling is a measurement process that determines the height of the level and the distance of an area with another elevated surface.

The principle of levelling is to obtain a horizontal line of sight at which the vertical distance of a point above or below this line of sight is found.

The main purpose of balancing in the survey is: Find the heights of the given points in relation to the given data.