Question
Define the terms:
- mineral.
- ore.
- gangue.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

| Column A | Column B |
| (1) Magnification | (a) $\frac{1}{f}$ |
| (2) Power of a lens | (b) $\frac{h_2}{h_1}$ |
| (3) Focal length | (c) $f$ |
| (4) Distance of an object from a lens | (d) $u$ |
| (e) $\frac{h_1}{h_2}$ |