Answer:
Approximately 
.
Explanation:
Cathode is where reduction takes place and anode is where oxidation takes place. The potential of a electrochemical reaction (
) is equal to
.
There are two half-reactions in this question. 
and 
. Either could be the cathode (while the other acts as the anode.) However, for the reaction to be spontaneous, the value of should be positive.
In this case, is positive only if is the reaction takes place at the cathode. The net reaction would be
.
Its cell potential would be equal to 
.
The maximum amount of electrical energy possible (under standard conditions) is equal to the free energy of this reaction:
,
where
is the number moles of electrons transferred for each mole of the reaction. In this case the value of is 
as in the half-reactions.
is Faraday's Constant (approximately 
.)
.
C is a non-metal and so is O. So the answer is CO
For astronomical objects, the time period can be calculated using:
T² = (4π²a³)/GM
where T is time in Earth years, a is distance in Astronomical units, M is solar mass (1 for the sun)
Thus,
T² = a³
a = ∛(29.46²)
a = 0.67 AU
1 AU = 1.496 × 10⁸ Km
0.67 * 1.496 × 10⁸ Km
= 1.43 × 10⁹ Km
