'''Methane''' is a [[chemical]] substance CH<sub>4</sub> found in a high percentage in [[natural gas]]. It is also a common byproduct of [[digestion]] in [[animal]]s.
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'''Methane''' is a [[chemical]] substance CH<sub>4</sub> found in a high percentage in [[natural gas]]. It is also a common byproduct of [[digestion]] in human and [[animal]]s.