If $AgI$ crystallises in zinc blende structure with $I^{-}$ ions at lattice points,what fraction of tetrahedral voids is occupied by $Ag^{+}$ ions? ............ $\%$

Consider an ionic solid $MX$ with $NaCl$ structure. Create a new unit cell $(Z)$ from the unit cell of $MX$ by following the sequential instructions given below. Ignore charge balance.
$(i)$ Remove all anions $(X)$ except the central one.
$(ii)$ Replace all face-centered cations $(M)$ with anions $(X)$.
$(iii)$ Remove all cations $(M)$ at the corners.
$(iv)$ Replace the central anion $(X)$ with a cation $(M)$.
The value of $\left(\frac{\text{number of anions}}{\text{number of cations}}\right)$ in $Z$ is . . . . .

Coordination number of $Na^{+}$ ion in rock salt is

The number of carbon atoms per unit cell of diamond unit cell is

Structure similar to zinc blende is found in

If the distance between $Na^{+}$ and $Cl^{-}$ ions in $NaCl$ crystal is $a \, pm$, what is the length of the cell edge?