The second is the obligation of memory.

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But Postmaster General Patrick Donahoe said the Postal Service would do whatever it takes to maintain its operations, even if that means defaulting on a second multibillion-dollar retiree obligation in as many months.

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Second, downward accountability is the obligation that the provider or the institution has to the learners.

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Second, once we have saved Social Security, we must fulfill our obligation to save and improve Medicare.

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