Bonus Task $21$: An aquifer is located between two reservoirs that are $55m$ apart from each

other. Concentrations in the reservoirs are $6\mathrm{.}5mo\frac{l}{k}g$ and ${25\mathrm{.}1}^{C_2}mo\frac{l}{k}g,$ respectively. What

is the concentration in $15m$ distance from the higher concentrated reservoir?

A: $11\mathrm{.}57$

B: $13\mathrm{.}35$

C: $5\mathrm{.}07$

D: $20$

E: $38\mathrm{.}3$