$\backslash$table$[[($c$)$ Two parallel flocculation basins are to be used to treat a raw water from River Y$.,,],[$The combined flow to the two tanks is $0\mathrm{.}1000\frac{m^3}{s}.$ The volume of each tank is$,,],[720m^3.$ Determine the detention time of each tank. Given the overflow rate of$,,],[$the tank is $20\frac{m^3}{d}.m^2,$ design the tank in meter $(m)$ if the width to the length ratio,,$],[$of the tank is $1$:$4,$ and the depth of the tank is within $3$ to $4\mathrm{.}5$ m$.,,],[,,$ marks$)]]$