A metal plate of area 2 ${\mathrm{m}}^2$ is pulled horizontally with a velocity of 0.5 ${\mathrm{ms}}^{-1}$ on a liquid layer 1 mm thick. The force required, if the viscosity of liquid is 12 N s ${\mathrm{m}}^{-2}$ is

• A

  1.2 N

• B

  12 N

• C

  12000 N

• D

  1200 N