When reversing a given reaction, we simply change the sign of the standard enthalpy change value. Therefore, the reaction will become:
H₂O → H₂ + 0.5O₂, ΔH = 286kJ
This is because if a certain amount of energy is released when a reaction occurs, the same amount of energy must be supplied for the reaction to occur in the reverse direction.
The correct answer is industrial smog. This type of smog exists in coal power plants which creates smoke and sulfur dioxide which may mix with fog creating a thick blanket of haze. Sulfur dioxide is one primary component of an industrial smog.
The answer would be 2.45 you know this
