Extracting a basis for the null space from parametric form — IITM BS previous year questions

Extracting a basis for the null space from parametric form is part of Null Space - Basis and Nullity, Week 5 in Mathematics 2. 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.