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Intake air containing 0.2% methane enters a section of an underground mine where emission of methane is 0.05m3/s. Assuming that the threshold limit value of methane is 1.25%, the minimum quantity of fresh air required in m3/s is

Intake air containing 0.2% methane enters a section of an underground mine where emission of methane is 0.05m3/s. Assuming that the threshold limit value of methane is 1.25%, the minimum quantity of fresh air required in m3/s is Correct Answer 4.70

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