Rahul and Sonia were playing with blocks and each of them made a train out of them. Both of them thought of measuring the length
of the train using their handspan. By that time Rahul's friend Anupam came and suggested they measure with a measuring tape for a fair result. (a) What is a handspan? (b) Why did Anupam ask both of them to use measuring tape? (c) Why a cubit cannot be used as the standard unit of length?
(a) The handspan is the distance between the tip of the thumb and tip of the little finger when the hand is fully stretched.
b) It is impossible for them to obtain an accurate result by the use of a handspan because it doesn't use any standard unit for measurement. It is entirely subjective and highly prone to human errors.