" In a closed packed array of "N" spheres,the numbers of tetrahedral holes are: "

In a close packed array of N spheres, the number of tetrahedral holes are

In a close packed array of N spheres, the number of tetrahedral holes are

In a close packed array of N spheres, the number of tetrahedral holes are

In a close pack array of n spheres, the number of tetrahedral holes are :

In aclosed packed array of N spheres ,the octahedral holes are :

In a metallic crystal with hexagonal close-packed arrangement of N atoms, the numbers of tetrahedral and octahedral voids are T and O, respectively, then-