River A converges with River $B$ and forms River $C$ at Point $P$ as shown in the figure. It is proposed to install in$-$stream aeration in River A to increase the dissolved oxygen $($DO$)$ to $6\mathrm{.}2m\frac{g}{L}$ just upstream of Point $P.$ If the aerator is capable of supplying an average of $0\mathrm{.}28lbD\frac{O}{?}$ day per linear $ft,$ the number of linear feet of aerators required to improve the water quality of River $A$ is most nearly:

A$.210$

B$.410$

C$.1,550$

D$.13,700$