Use the Darcy's equation, Colebrook$-$White equation, formulas, tables and relevant information from Lecture Notes$-$Chapter $1.$

$1\mathrm{.}1$ Water flows from the ground floor to the second level in a three$-$storey building through a $20mm$ diameter pipe $($drawn$-$tubing, pipe roughness $E=0\mathrm{.}0015mm)$ at a rate of $0\mathrm{.}75$lite$\frac{r}{s}$ as shown in Fig$\mathrm{.}1\mathrm{.}1.$ The layout of the whole system is illustrated in Figure below. The water flows out from the system through a valve with an opening of diameter $12\mathrm{.}5mm.$ Determine, the gage pressure at point $(1).$ Take dynamic viscosity, $1\mathrm{.}12{10}^{-3}$ Pas.