embankment on the centre line

excavation on the centre line

earth work on the centre line

none of these.

positive compensating error

negative compensating error

positive cumulative error

negative cumulative error.

linear measurements only

angular measurements only

both linear and angular measurements

none of these.

line of sight is horizontal

axis of the telescope is horizontal

line of collimation is horizontal

geometrical axis of the telescope is horizontal.

the power of a lens is the reciprocal of its focal length

the unit of power of the lens is diopter

the power of two or more thin lenses in contact is the power of the combination of the lenses

All of these