b$)$ The performance of a double$-$chamber MFC with anode surface area and volume of $7\mathrm{.}065{10}^{-4}{m}^2$ and $0\mathrm{.}028L$ respectively have been evaluated. Resistance of $1000$ and glucose concentration of $0\mathrm{.}6\frac{g}{L}$ have been used. For experiments with PEM, the voltage increases up to $0\mathrm{.}5V$ and drops to $0\mathrm{.}25V$ over $95$ hours. Without PEM, the voltage increases rapidly up to $0\mathrm{.}7V$ and decreases to $<mn\; id="EditorElement\_599977">0</mn><mn\; id="EditorElement\_599978">.</mn><mn\; id="EditorElement\_599979">0</mn><mn\; id="EditorElement\_599980">5</mn><mi\; id="EditorElement\_599982">V</mi>$ within $15$ hours. Find out average power and current for the MFC running with and without PEM. Also determine the Coulombic efficiency for the MFC with and without PEM.

Faraday's constant is $96485$ C$/$mol electron.