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.

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 $..............$.

$A$ large cylindrical tank of cross-sectional area $1\ m^2$ is filled with water. It has a small hole at a height of $1\ m$ from the bottom. $A$ movable piston of mass $5\ kg$ is fitted on the top of the tank such that it can slide in the tank freely without friction. $A$ load of $45\ kg$ is applied on the top of the water by the piston,as shown in the figure. The value of $v$ when the piston is $7\ m$ above the bottom is $(g = 10\ m/s^2)$ ....... $m/s$

In the following figure,the flow of liquid through a horizontal pipe is shown. Three tubes $A, B$ and $C$ are connected to the pipe. The radii of the tubes $A, B$ and $C$ at the junction are respectively $2 \ cm, 1 \ cm$ and $2 \ cm$. It can be said that the:

Water is flowing in streamline motion through a horizontal tube. The pressure at a point in the tube is $p$ where the velocity of flow is $v$. At another point, where the pressure is $p/2$, the velocity of flow is (density of water $= \rho$)

Two light balls are suspended as shown in the figure. When a stream of air passes through the space between them,the distance between the balls will