Question

What are the problems of using different parts of the body as an instrument to measure length?

Answer 1

Different people use hand for measuring length.but some people have big hand and some have short, the measurement can be wrong

Answer 2

For measuring anything the instruments used for that purpose should be of standard length which is same everywhere but this thing cannot be done with help of the different body parts because everyone on this Earth don't have same length/measurement of hands, spans, legs, etc.

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