Which type of void is present in body centred cubic lattice

Q. The number of atoms present in a unit cell of a monoatomic substance (element) of a simple cubic lattice, body-centred cubic and face centred cubic, respectively, are___________.

Q. In a simple cubic lattice of anions, the side length of the unit cell is $2.88$ $\stackrel{\circ }{A}$. The diameter of the void in the body centre is:

Q. In a simple cubic lattice of anions, the side length of the unit cell is $3.0\stackrel{o}{A}.$ The diameter of the void in the body centre is

Q. $N{H}_{4}Cl$ crystallizes in a body-centred cubic type lattice with a unit cell edge length of $387$ pm. The distance (in pm) between the oppositely charged ions in the lattice is:

Q. There are three ionic compounds, first compound has fcc lattice of anions and cations are present in all tetrahedral voids, second compound has fcc lattice of anions and cations are present in all octahedral voids and the third compound has simple cubical lattice in which cubical void is occupied by cation, then the order of packing efficiency of these will be :