A Mixed Flow Reactor is filled with $10$ L of an aqueous solution of A$.$ When the

concentration of A inside the reactor is $1$ mol$/$L$,$ and an aqueous solution containing

A at a concentration of $0\mathrm{.}1$ mol$/$L is fed into the reactor at $2$ L$/$min while

simultaneously extracting $2$ L$/$min from the reactor: $1)$ Calculate the time required for the concentration of A inside the reactor to

decrease to $10\%$ of its initial concentration if A does not react. $2)$ Calculate the time required if A decreases according to the rate $-$rA $($mol$/$L$$min$)$

$=0\mathrm{.}2($min$-1)$CA$($mol$/$L$),$ assuming there is no change in the density of the solution

due to concentration changes.