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

Water flows in a horizontal tube (see figure). The pressure of water changes by $700 \; Nm^{-2}$ between $A$ and $B$ where the area of cross-section are $40 \; cm^{2}$ and $20 \; cm^{2},$ respectively. Find the rate of flow of water through the tube in $cm^{3} / s$. (Density of water $= 1000 \; kgm^{-3}$)

State Bernoulli's principle in words.

Water is flowing in a streamline manner in a horizontal pipe. If the pressure at a point where the cross-sectional area is $10 \,cm^2$ and velocity is $1 \,m/s$ is $2000 \,Pa$, then the pressure of water at another point where the cross-sectional area is $5 \,cm^2$ is: (in $\,Pa$)

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.

$Assertion :$ The pressure of water increases when it flows from a narrow pipe to a wider pipe.
$Reason :$ According to the equation of continuity,$A_1v_1 = A_2v_2$,and by Bernoulli's principle,where velocity is high,pressure is low.