Which crystal system does diamond possess?

The angle between $(100)$ and $(110)$ planes of an $FCC$ lattice is: (in $^{\circ}$)

The number of atoms present in a unit cell of a monoatomic substance with a simple cubic lattice is:

If the distance between $Na^{+}$ and $Cl^{-}$ ions in sodium chloride crystal is '$Y$' $pm$, the length of the edge of the unit cell will be:

Which primitive unit cell has unequal edge length $(a \ne b \ne c)$ and all axial angles different from $90^{\circ}$?

$A$ metal has a $bcc$ structure. If the edge length of its unit cell is $3.04 \ \overset{\circ}{A}$,what is the volume of the unit cell in $cm^3$?