An oil tanker breaks apart and starts leaking. Suppose that right after the shipwreck, the oil is leaking out at a rate of 0.2 million gallons per minute, and that the rate decays exponentially with a half-life of 140 minutes. Then, minutes after the shipwreck the oil is leaking at a rate of million gallons per minute, and million gallons of oil will leak out in the first 230 minutes after the shipwreck.

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