Questions marked board paper are copied from the official papers — CBSE 2026-27 Sample Question Paper.pdf with CBSE 2026-27 Marking Scheme.pdf (18); CBSE 2025-26 Sample Question Paper.pdf with CBSE 2025-26 Marking Scheme.pdf (15) — and each answer from that paper’s own marking scheme. One was only kept when the marking scheme’s wording matched the option it names, so none of those answers is anyone’s guess. Questions needing a diagram the text cannot carry were left out, and a question asked in more than one session appears once. Questions marked from your notes are built from these notes’ own 60-second recall tables and verbatim definitions — every stem, option and answer lifted word for word from a chapter, nothing written by a model. They are drill, not past board questions, which is why the two are labelled separately and never blended. The pool does not run out: when you reach the end it starts again with whatever you got wrong at the front, and the options in a new order.