Surveying
To avoid large centering error with very short legs, observations are generally made

To a target fixed on theodolite tripod on which theodolite may be fitted easily
To chain pins
By using optical system for centering the theodolite
All listed here

ANSWER DOWNLOAD EXAMIANS APP

Surveying
The meridian of a place is

A semi-circle which passes through the place and is terminated at the poles
An arc of the great circle which passes through the place and is perpendicular to the equator
A great circle passing through the place and the poles
A great circle whose plane is perpendicular to the axis of rotation and it also passes through the place

ANSWER DOWNLOAD EXAMIANS APP