Two parallel plates, with Newtonian incompressible liquid in between, are 2 mm apart. The upper plate is stationary and the lower plate moves with a velocity of 4 m/s. A force per unit area of 5 N/m2 is applied parallel to the lower plate to maintain its motion. The viscosity of the liquid (rounded off to two decimal places) is ______ \(\times10^{-3}\) N.s/m2.