The included angles of a theodolite traverse, are generally measured ............

The lines passing through points at which the magnetic declination is equal at a given time are called ............

A level line is ............

The rise and fall method of reduction of levels, provides a check on ............

In a theodolite the line of collimation is ............

In tacheometrical observations, vertical staff holding is generally preferred to normal staffing, due to ............

The height of instrument is equal to ............

Which of the following methods of offsets involves less measurements on the ground?

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