Given that,
The equation is :
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To find,
The missing coefficients.
Solution,
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Let the value of ? is x.
It is the equation of photosynthesis.
In LHS,
Carbon atoms = 6
Hydrogen atom = 12
Oxygen atom = 18
In RHS,
Carbon atoms = 6
Hydrogen atom = 12
Oxygen atom = 6
If we make the equation as
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No the number of atoms in RHS = 6+ 12 = 18
It means if we take the value of ? as 6 the equation will be balanced.
Hence, the correct option is (B) "6".