What are the coordination numbers of $bcc$,$scc$,and $fcc$ respectively?

$A$ crystal is formed by two elements $X$ and $Y$ in a cubic structure. $X$ atoms are at the corners of a cube,while $Y$ atoms are at the face centers. The formula of the compound will be:

Which statement is correct for the antifluorite structure of $Na_2O$?

In which of the following structures,the anion has the maximum coordination number?

The coordination number of $Cs^+$ in the crystal of $CsCl$ is ......

In a crystal of $NaCl$, the distance between $Na^{+}$ and $Cl^{-}$ is $x \, pm$. What is the edge length of the unit cell?