Profile levelling is usually done for determining

A relatively fixed point of known elevation above datum, is called

While measuring a chain line between two stations intervened by a raised ground

The total number of zeroes graduated on a surveyors compass is

The angle between two plane mirrors of optical square, is

The zero of the graduated circle of a prismatic compass is located at

The imaginary line joining the points if zero declination on the surface of the earth is called as

Number of links per meter length of a chain are

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