In a crystal lattice,the number of octahedral voids compared to tetrahedral voids is ...............

$Ag$ crystallises in $fcc$ lattice. What is the total number of tetrahedral voids present in $540 \ g$ of $Ag$ metal (in $N_A$)? $(N_A = \text{Avogadro number}; Ag \text{ atomic weight} = 108 \ g \ mol^{-1})$

In a simple cubic lattice,what percentage of the space is left unoccupied by the spheres?

In a crystal,atoms of $A$ form an $FCC$ lattice,atoms of $B$ occupy all octahedral voids,and atoms of $C$ occupy $25\%$ of the tetrahedral voids. The possible molecular formula of the compound is:

The void space in an $fcc$ structure is ..........

What is the percentage of unoccupied space in $fcc$ unit cell (in $\%$)?