A 1 -megabit computer memory chip contains many $60.0-\mathrm{fF}$ capacitors. Each capacitor has a plate area of $21.0 \times 10^{-12} \mathrm{m}^{2} .$ Determine the plate separation of such a capacitor (assume a parallel-plate configuration). The order of magnitude of the diameter of an atom is
$10^{-10} \mathrm{m}=0.1 \mathrm{nm} .$ Express the plate separation in nanometers.