Example:

The diameter of a water pipe changes gradually from $150$ mm at point A to $75$ mm at point $B$ as shown below. Point $A$ is $6$ m above the datum and point $B$ is $3$ m above the datum. The pressure at point A is $103k\frac{N}{m^2}$ and the velocity of flow is $3\mathrm{.}6\frac{m}{s}.$ Determine $($i$)$ the velocity and $($ii$)$ the pressure at point B$.$ Density for water, ${}_{\text{w}\text{a}\text{t}\text{e}\text{r}}$ can be taken as $1000k\frac{g}{m^3}$

A