When a chain is used at a temperature more than the temperature it was calibrated, the error in measured length will be

The box of prismatic compass is made of

The principle of optics used in the construction of an optical square is

A tape of length l and weight 'w' kg/m is suspended at its ends with a pull of P kg, the sag correction is,

The least count of a vernier scale is

If 'n' is the number of sides, then the total sum of interior angles of a closed traverse should be

The working edge of an alidade, is known as

In order to determine the natural features such as valleys, rivers, lakes etc., the surveying preferred is

In order to locate a point by oblique offsets we must measure and note at least