The distance between terminal points computed from known, as ............

A pass or a saddle in a mountainous region ............

Cross staff is an instrument used for ............

The approximate formula for radial or perpendicular offsets from the tangent, is ............

Drop arrow is used in ............

A 15 cm theodolite means ............

The horizontal equivalent which is a term generally uses in contoured map is ............

Contours of different elevations may cross each other only in the case of ............

In chain surveying field work is limited to ............