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

Two pipes of radii $2 \, cm$ and $4 \, cm$ are connected in series. What is the ratio of the flow velocities of the fluid in these pipes?

Water coming out of the mouth of a tap and falling vertically in streamline flow forms a tapering column,i.e.,the area of cross-section of the liquid column decreases as it moves down. Which of the following is the most accurate explanation for this?

An incompressible fluid (ideal fluid) is flowing through a non-uniform cross-sectional tube $PQ$ from end $P$ to end $Q$. If $K_P$ and $K_Q$ are the kinetic energy per unit volume of the fluid at end $P$ and end $Q$ respectively, then

In a streamline flow,

The radius of the cross-section of the cylindrical tube of a spray pump is $2 \,cm$. One end of the pump has $50$ fine holes, each of radius $0.4 \,mm$. If the speed of flow of the liquid inside the tube is $0.04 \,ms^{-1}$, what is the speed of ejection of the liquid from the holes (in $\,ms^{-1}$)?