Question $3.$ The stream flows due to three successive storms of $2\mathrm{.}1,3\mathrm{.}6$ and $2\mathrm{.}85cm$ of $6$

hours duration each on a basin are given below. The area of the basin is

$483\mathrm{.}6k{m}^2.$ Assuming a constant base flow of $10$ cumec, and an average

storm loss of $0\mathrm{.}1c\frac{m}{h}r,$

a$)$ Derive $6-$hour unit hydrograph

b$)$ Provide the plots of storm event$1,2,3$ and combined storm graphs with

the derived the $6-$hour unit hydrograph

c$)$ Derive $3-$hour and $9-$hour unit hydrograph using S$-$curve method

d$)$ Display $3-$hour, $6-$hour, $9-$hour unit hydrograph together including the S$-$

curve ordinate and lagged S$-$ curve ordinate together

Mark allocated:$20$