Correct Answer – D
Number of octahedral sites `=` Number of ions in the packing.
`:.` Number of octahedral sites per sphere `= 1`

Correct Answer – a
Number of ncubedral sites = Number in the packing
`:.` Number of ocubedral slkites per sphere `= 1`

Correct Answer – C

Correct Answer – d
No. of octahedral sites = No. of ions in the packing . `therefore` No. of octahedral sites per sphere =1

Correct Answer – 1
In any close packing , no of spheres is equal to no . Of octahedral holes.