The airline improved its key financial metric of passenger revenue per available seat mile (or PRASM) by 5.5% year-over-year, according to a statement.

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The "cubic mile of oil"--a metric roughly equivalent to the amount of oil consumed worldwide each year--is frequently used to explain the challenge facing solar, wind, geothermal and biomass power.

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The goal, when the system is completed in 2015, will be to capture 1 million metric tons a year of carbon dioxide and inject it a mile underground.

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