A contour map of the area is essential before proceeding with the construction of

An imaginary line on the surface of the earth having a constant inclination with the horizontal (slope) is called

The included angles of a theodolite traverse, are generally measured

To orient a plane table at a point with two inaccessible points, the method generally adopted is

The angle of intersection of a contour and a ridge line, is

The permissible limits of error in chaining for measurement on rough of hilly ground is

The length of an Engineer's chain is

The combined correction for refraction and earth's curvature (in levelling observations) is

The degree of the curve is the angle subtended by a chord of length.