What is the full form of $fcc$?

What is the percentage of space occupied in a $bcc$ arrangement (in $\%$)?

For a simple cubic $(SC)$,body-centered cubic $(BCC)$,and face-centered cubic $(FCC)$ unit cell with edge length $a$,what is the ratio of the radii of the atoms present in them?

What is the minimum number of spheres required to develop a tetrahedral void?

The stacking pattern in a body-centered cubic $(bcc)$ lattice is of the type............

Calculate the void volume of a simple cubic unit cell if the volume of the unit cell is $5.5 \times 10^{-22} \ cm^3$.