$7\mathrm{.}4$ The settling basin for a type$-1$ suspension is to operate at an overflow rate of $0\mathrm{.}76$ m$3/$m$2$ h$.$ The flow rate through the plant is $24,000$ m$3$

$/$day$.$ Determine the dimensions for a long rectangular basin,

using a length to width ratio of $4$:$1.$ Depth should not exceed $4$ m$.$

Use more than one tank. Determine the detention time in the tank

and the horizontal velocity.