The figure represents vertical sections of four wings moving horizontally in air. In which case is the force upwards?

Obtain Bernoulli's equation for a fluid at rest.

Glycerine of density $1.25 \times 10^3 \, kg \, m^{-3}$ is flowing through a conical section of a pipe. The area of cross-section of the pipe at its ends is $10 \, cm^2$ and $5 \, cm^2$, and the pressure drop across its length is $3 \, N \, m^{-2}$. The rate of flow of glycerine through the pipe is $x \times 10^{-5} \, m^3 \, s^{-1}$. The value of $x$ is $..............$.

What type of fluid can be applied in Bernoulli's equation?

As shown in the figure, a pump is designed as a horizontal cylinder with a piston having area $A$ and an outlet orifice having an area $a$. The piston moves with a constant velocity under the action of force $F$. If the density of the liquid is $\rho$, then the speed of the liquid emerging from the orifice is (assume $A \gg a$):

The figures below show water flowing through a horizontal pipe from left to right. Note that the pipe in the middle is narrower. Choose the most appropriate depiction of water levels in the vertical pipes.