$($Step$-$Input to Determine $E(t)$ in CSTR$)$ Starting from $t=0,$ the tracer enters the

CSTR with concentration $C_0.$ The volumetric flow rate for both inlet and outlet

is maintained at $V_0.=\frac{V}{V_0}.$

a$)$ Express $E(t)$ in terms of $t$ and $.$ Hint: $V_0{C}_{0}dt=V_{0}C(t)dt+VdC(t)$

b$)$ What's the fraction of effluent that has been in the reactor for less than time $?$