Consider a laminar flow in the x-direction between two infinite parallel plates (Couette flow). The lower plate is stationary and the upper plate is moving with a velocity of 1 cm/s in the x-direction. The distance between the plates is 5 mm and the dynamic viscosity of the fluid is 0.01 N-s/m². If the shear stress on the lower plate is zero, the pressure gradient, ∂p/∂x (in N/m² per m, round off to 1 decimal place) is _______.