Q.Distinguish between

Step 1 – Hexagonal vs monoclinic unit cells.

So a hexagonal cell has two equal edges with a $120^\circ$ angle between them, while a monoclinic cell has all three edges unequal with only one angle different from $90^\circ$.

Step 2 – Face-centred vs end-centred unit cells.

• Face-centred (fcc): constituent particles are present at all 8 corners and at the centre of every one of the 6 faces. …

For (i) compare the crystal-system axial lengths and angles side by side. For (ii) compare where the extra (non-corner) particles sit — all six fa …

• Writing $\gamma=90^\circ$ for hexagonal; the defining angle is $\gamma=120^\circ$.
• Saying monoclinic has all angles $90^\circ$; exactly one angle ($\beta$) differs from $90^\circ$. …