Is viscosity a vector or a scalar?

The viscous force between two liquid layers is

$A$ metal block of base area $0.20\,m^2$ is placed on a table,as shown in the figure. $A$ liquid film of thickness $0.25\,mm$ is inserted between the block and the table. The block is pushed by a horizontal force of $0.1\,N$ and moves with a constant speed. If the viscosity of the liquid is $5.0 \times 10^{-3} \,Pa-s$,the speed of the block is $.........\times 10^{-3}\,m/s$.

Write one practical use of viscosity.

For the situation shown in the figure,water flows on the surface of a fixed plate. The velocity of water as a function of distance $y$ is given as: $u = \alpha \left[ \frac{y}{h} - 2\left( \frac{y}{h} \right)^2 \right]$. Determine the magnitude of the shear stress that the water applies at the base of the plate. The coefficient of viscosity is $\eta$.

Water is flowing steadily in a river. $A$ and $B$ are two layers of water at heights $40 \ cm$ and $90 \ cm$ from the bottom. The velocity of layer $A$ is $12 \ cm/s$. If the velocity of the water at the bottom is $0$,what is the velocity of layer $B$ (in $cm/s$)?