How many lattice points are present in a face-centred cubic unit cell?

For which of the following substances will $a \ne b \ne c$ and $\alpha = \beta = \gamma = 90^o$ $NOT$ hold true?

Identify the crystal system in which a primitive unit cell has edge lengths $a = b = 200 \text{ pm}$ and $c = 300 \text{ pm}$ and all axial angles are $90^{\circ}$.

Maximum possible number of three-dimensional and two-dimensional lattices are respectively:

$A$ solid compound $XY$ has $NaCl$ structure. If the radius of the cation is $100 \ pm,$ the radius of the anion $(Y^-)$ will be .............. $pm$.

The parameters of the unit cell of a substance are $a=2.5, b=3.0, c=4.0, \alpha=90^{\circ}, \beta=120^{\circ}, \gamma=90^{\circ}$. The crystal system of the substance is :