which of the following is /are correct?
A. In (hcp) unit cell, the total number of octahedral voids is 4.
B. The third nearest neighbour of `Na^(+)` in `NaCl` is `8Cl^(-)` ions .
C. The rank of ZnS unit cell is four (4).
D. The (hcp)unit cell the total number of tetrahedral void is 12.
