James has a mass of $87$ kg and his resting metabolic rate is about $139$ watts, or about $118$ kcal per hour. Suppose that James immerses himself in a tub containing $84$ liters of water at a starting temperature of $0$ C

and then maintains a metabolic rate equal to twice his normal resting metabolic rate until all of the water reaches his normal body temperature of $37$ C.

$.$

How long would it take to heat the water to $37$ C?

 

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