Calculate the number of atoms in a fcc unit cell.

Explanation

(i) The atoms in the face centre is being shared by two unit cells each atom in the face centers makes `((1)/(2))` contribution to the unit cell.
` :.` Number of atoms in a fcc unit cell.
`= ( N_(c )) /( 8) + ( N_(f))/( 2)`
` = ( 8)/(8) + ( 6)/( 2)`
`= 1+ 3 `
`= 4`