Standard deviation - σ (population) and s (sample); unit interpretation — IITM BS previous year questions

Standard deviation - σ (population) and s (sample); unit interpretation is part of Measures of Dispersion (L3.4), Week 3 in Statistics 1. Prasnya files every IIT Madras BS previous year question from this subtopic here, each one with a worked explanation. Take the whole set as a timed mock and you get accuracy, pacing and per-question analysis back.