In indirect method of contouring, the best method of interpolation of contours is

The difference in the lengths of an arc and its subtended chord on the earth surface for a distance of 18.2 km, is only

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

An ideal vertical curve to join two gradients, is

Invar tapes are made of an alloy of

When the length of a chord is less than the peg interval, it is known as

The working edge of an alidade, is known as

Direct ranging is possible only when the end stations are

The constant vertical distance between two adjacent contours, is called