The angle between the reflecting surface of a prism square is ............

During leveling if back sight is more than foresight ............

Contour interval, within the limits of a map ............

The value of additive constant for the tacheometer varies from ............

Rankine's deflection angle in minutes is obtained by multiplying the length of the chord by ............

Reciprocal leveling eliminates ............

A deflection angle in a traverse is equal to the ............

If the fore bearing of a line is 36°15', its back bearing will be ............

True meridians are generally preferred to magnetic meridians because ............