Data and information for Problems $1-3.$

The design flow for a water treatment plant is $7\mathrm{.}6{10}^3\frac{m^3}{?}$ day. For coagulant addition, a rapid mix tank will have a mechanical mixer, and the average dose of alum coagulant will be $30m\frac{g}{L}.$ The theoretical mean hydraulic retention time of the rapid mix tank will be $30$ seconds. Determine the following.

The quantity of alum needed on a daily basis, in units of $k\frac{g}{?}$ day, is most nearly?

A$.2\mathrm{.}28{10}^{-1}$

B$.2\mathrm{.}28{10}^2$

C$.5\mathrm{.}03{10}^2$

D$.2\mathrm{.}28{10}^5$

E$.5\mathrm{.}03{10}^5$

For a rapid mix tank with equal length, width, and depth, the dimensions of the rapid mix tank $($in meters$),$ should be most nearly.

A$.1\mathrm{.}4$

B$.1\mathrm{.}6$

C$.2\mathrm{.}6$

D$.5\mathrm{.}4$

E$.61$

If the water temperature is $5C,$ the power input $($in $kW)$ required needed to achieve a velocity gradient of $900se{c}^{-1}$ is most nearly?

A$.2\mathrm{.}8$

B$.3\mathrm{.}2$

C$.32$

D$.2,800$

E$.3,200$