For α − Fe with a bcc structure having a lattice parameter a = 2.8665 A , calculate the mass density (in g/cm³) and atomic density (in atoms/cm³) of the material.
A) Mass density: 6.905 g / cm³, Atomic density: 2.479 × 10^22 atoms / cm³
B) Mass density: 7.874 g / cm³, Atomic density: 5.636 × 10^22 atoms / cm³
C) Mass density: 8.364 g / cm³, Atomic density: 3.583 × 10^22 atoms / cm³
D) Mass density: 7.874 g / cm³, Atomic density: 7.166 × 10^22 atoms / cm³