What is the total number of unit cells shared by each corner particle of bcc unit cell?

Calculate the number of particles present per unit cell if mass of a particle is $8.0 \times 10^{-23} \mathrm{~g} \left[\rho \times a^3=3.2 \times 10^{-22} \mathrm{~g}\right]$

Calculate the edge length of unit cell if a metal with atomic radius 128 pm forming fcc unit cell structure.

Which of the following dopant is used in silicon to produce p-type semiconductor?