Two metal plates $(A, B)$ are kept horizontally with a separation of $(\frac{12}{\pi}) \text{ cm}$, with plate $A$ on the top. An atomizer jet sprays oil (density $1.5 \text{ g/cm}^3$) droplets of radius $1 \text{ mm}$ horizontally. All oil droplets carry a charge of $5 \text{ nC}$. The potentials $V_A$ and $V_B$ are required on plates $A$ and $B$ respectively in order to ensure the droplets do not descend. The values of $V_A$ and $V_B$ are . . . . . . . (Neglect the air resistance to the droplets and take $g = 10 \text{ m/s}^2$)

• A
  $100 \text{ V}$ and $580 \text{ V}$
• B
  $580 \text{ V}$ and $100 \text{ V}$
• C
  $60 \text{ V}$ and $400 \text{ V}$
• D
  $0 \text{ V}$ and $-200 \text{ V}$