For some crystals,the radius ratio for cation and anion is $0.525$,its coordination number will be

In an ${A^{+}}{B^{-}}$ ionic compound, the radii of ${A^{+}}$ and ${B^{-}}$ ions are $180 \ pm$ and $187 \ pm$ respectively. The crystal structure of this compound will be:

Which one possesses an antifluorite structure?

For an ionic crystal with the general formula $AX$,the coordination number is $6$. What is the radius ratio range?

In a cubic structure of a compound made from $X$ and $Y$,where $X$ atoms are at the corners of the cube and $Y$ atoms are at the face centers of the cube,the molecular formula of the compound is:

If the number of atoms per unit cell in a crystal is $2$,the structure of the crystal is: