$($b$)$ Table $4$ shows the $1-$hr unit hydrograph $($UH$)$ for Sungai Perlis basin.

Uadual $4$ menunyukan I$-$fam unit hidrograf $($UY$)$ tagi tenbangan Singai Perils.$]$

Table $4$: $1-$hr Unit Hidrograph

$[$Jadual A: I Iaam Unir Hidrogra$]?$

$\backslash$table$[[$Time $($hr$),0,1,2,3,4,5,6,7,8,9,10],[$UH $(1-$hr$),0,25,50,100,80,60,40,20,0,0,0]]$

Transform this hydrograph data to a $3-$hr UH and sketch the graphs. $[$Tikarkan data hidrograf ini kepada $3-$jan UH$.]$

$(6$ Marks$/$ Markah$)$

ii$)$ Evaluate and convert the S$-$curve ordinate to UH$-3$Hr$.$

$[$Nilai dan tukarkan ordinat lenghung$-$Skepada UH$-3$Jam$]$

$(6$ Marks$/$ Markah$)$

iii$)$ Sketch the UH$-2$Hr and UH$-3$Hr graph and examine the Qp and tb for both UH graph.

$[$Lakarkan graf UH$-2$Jam dan UH$-3$Jam dan periksa nilai Qp dan to bagi kedua$-$dua graf UH$]$

$(4$ Marks$/$ Mankah$)$