When water falls from a tap,what happens to the cross-sectional area of the water stream as it moves downwards?

Explain streamline and streamline flow.

$A$ pipe having an internal diameter $D$ is connected to another pipe of the same size. Water flows into the second pipe through $n$ holes, each of diameter $d$. If the water in the first pipe has speed $v$, what is the speed of water leaving the second pipe?

The figure below shows a liquid being pushed out of a tube by a piston having a cross-sectional area of $2.0\,cm^2$. The cross-sectional area at the outlet is $10\,mm^2$. If the piston is pushed at a speed of $4\,cm/s$,the speed of the outgoing fluid is $.........\,cm/s$.

An engine pump ejects a liquid of density $\rho$ through a pipe of cross-sectional area $A$. If the velocity of the liquid coming out of the pipe is $v$,find the rate at which kinetic energy is imparted to the liquid.

Give an example of steady flow.