Water Smart Sdn Bhd has been assigned to construct a water distribution from Rajang River to several longhouses in Sarawak which are currently resided by $100$ people. Water from the river is pumped at a rate of $200\frac{L}{s}$ to a tank as shown in FIGURE Q$3.$ The pipe is $90m$ in length and made of $4-$in$,$ Schedule $40$ commercial steel pipe. In the pipeline, there are three gate valves, one globe valve and two $90$ long$-$radius elbows. The surface of the water in the tank is $6m$ above the river. The vapor pressure in the tank is $50$kPa.

FIGURE Q$3$: Pipeline system from the river to tank

a$.$ Estimate the head loss in the pipeline. State TWO $(2)$ assumptions.

$[12$ marks$]$

b$.$ Predict the pump work required if the efficiency of the pump is $65\%.$

$[4$ marks$]$

c$.$ Discuss on the system operation to ensure continuous supply of water to the residents in longhouses.

$[4$ marks$]$