Consider fully developed, steady state incompressible laminar flow of a viscous fluid between two large parallel horizontal plates. The bottom plate is fixed and the top plate moves with a constant velocity of $\text{U= 4 m/s}$. Separation between the plates is $\text{5 mm}$. There is no pressure gradient in the direction of flow. The density of fluid is $\text{800 kg/m$^{3}$}$ and the kinematic viscosity is $1.25 \times 10^{-4} m^{2}/s$. The average shear stress in the fluid is _____ $\text{Pa}$ ($\textit{round off to the nearest integer}$).