Levelling MCQ with answer and solution

Concept

Sights taken at a change point

Step-by-step solution

1. A turning point is a staff station where the instrument is shifted. 2. A foresight is taken on it before the shift and a back sight after the shift.

Explanation

Turning points (change points) link two instrument positions, so both a foresight and a backsight are taken on them. Intermediate sights are taken only on points between the first and last readings of a setup.

Shortcut

Turning point → FS + BS.

Common mistake

Choosing foresight only.