Consider Base Centered Cubic $($BCC$)$ Molybdenum $($Mo$)$ crystal structure with an atomic radius $r_{M_0}=0\mathrm{.}139nm.$ The side of the cubic unit cell is a $=0\mathrm{.}321nm.$

The linear density along $[110]$ is $$ atoms$/$nm

The linear density along $[111]$ is $$ atoms$/$nm

The planar density in the plane $(101)$ is

$$ atoms $\frac{?}{n{m}^2}$

The planar density in the plane $(111)$ is

$$ atoms $\frac{?}{n{m}^2}$