$A$ parallel plate capacitor has a potential of $20 \, kV$ and a capacitance of $2 \times 10^{-4} \, \mu F$. If the area of the plates is $0.01 \, m^2$ and the distance between the plates is $2 \, mm$,find the energy stored in the capacitor.

• A
  $4 \times 10^{-7} \, J$
• B
  $2 \times 10^{-5} \, J$
• C
  $5 \times 10^{-5} \, J$
• D
  $4 \times 10^{-2} \, J$