A tubular reactor is used to produce a commercially important chemical D at a total pressure of $5+5100$ kN$/$m$^2$ in an exothermic equilibrium reaction: A$+$BC$+$D

An equimolar mixture of A and B of concentration $0\mathrm{.}01$ kmol$/$s is fed to the reactor and plug flow conditions prevails within the reactor. What are the optimal isothermal temperature for operation and the corresponding reactor volume for a final fractional conversion of $0\mathrm{.}68?$ Is this the best way of operating the reactor? Data: Assume the reactions as second order reactions and $4=4\mathrm{.}4\backslash$times $10^3$

exp$(-105\backslash$times $10/$RT$)$