Question

While measuring length using a metre scale, the position of the eye
(a) should be vertically above the 0-mark of the scale.
(b) should be vertically above the point where the measurement is to be taken.
(c) should be a little away from the point where the measurement is to be taken.
(d) does not matter as long as the scale is accurate.

Answer 1

(b) should be vertically above the point where the measurement is to be taken.

The eye must be vertically above the point where the measurement is to be taken to avoid parallax error.