Problem $2(20$ pts$)$

A CSTR of volume $V_L$ is used to carry out an irreversible isothermal reaction: $DE.$ The reactor is initially empty. A solution of species $D$ at concentration $C_D$ starts to flow into the reactor at a constant volumetric flow rate of $F_{in}$ when time $=0.$ No liquid is allowed to leave the reactor until the liquid volume reaches a value of $V_L.$ The rate of reaction is given by the first order reaction $r=k^{**}{C}_D$

Sketch the flow diagram of the reactor. $5$ pts

Express the concentration of species $D$ within the reactor as a function of time. $15$ pts