Approximately how much more free energy is supplied to the electron transport chain by nadh than by fadh2?

Is supplied aproximately two more electrons by NADH than by FADH2.

FADH2 enters the electron transport chain later than NADH. The electron transport chain is made of protein complexes and the passage of an electron through each complex releases a H+ across the membrane. The movement of these H+ creates potential energy as electrochemical gradient that will later generate energy for the enzyme ATP synthase to produce ATP. NADH starts giving these electrons at an earlier stage than FADH2 supplying more energy to the electron transport chain.

The answer would be a. aluminum can