The ratio of anion radius to cation radius of a crystal is $10 : 9.3$. Then, the coordination number of the cation in the crystal is

Which of the following is correct for the crystal lattices mentioned below?

In a face centred cubic lattice,atom $A$ occupies the corner positions and atom $B$ occupies the face centre positions. If one atom of $B$ is missing from one of the face centred points,the formula of the compound is:

$A$ binary compound $(A^{+} B^{-})$ has a zinc blende structure where $B^{-}$ ions form the lattice and $A^{+}$ ions occupy $25\%$ of the tetrahedral voids. What is the formula of the compound?

How does the structure of $NaCl$ transform into the $CsCl$ structure?

$A$ compound made of elements $A$ and $B$ forms an $fcc$ structure. Atoms of $A$ are at the corners and atoms of $B$ are present at the centres of the faces of the cube. What is the formula of the compound?