In his career, Manning Marable wrote about the struggle for equal rights — and especially the life of Malcolm X. In this file photo from 2001, he posed at his Columbia University office in New York. Mario Tama/Getty Images hide caption

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Emergency vehicles leave the entrance to Massey Energy's Upper Big Branch coal mine in Montcoal, W.Va., on April 5, 2010, after a deadly explosion. Jeff Gentner/AP hide caption

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This shipping container was discovered upside down on the seafloor by researchers in June 2004, four months after it was lost at sea. Monterey Bay Aquarium Research Institute hide caption

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President Obama participates in an AARP tele-town hall on health care in July 2009. The seniors group lobbied hard for the president's health care law. Now, Republicans say the group stands to make a healthy profit from the law. Haraz N. Ghanbari/AP hide caption

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An oil drilling rig is seen near Ray, N.D., last September. The well is being drilled into the Bakken Formation, one of the largest contiguous deposits of oil and natural gas in the United States. Karen Bleier/AFP/Getty Images hide caption

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A woman walks by a "Help Wanted" sign taped to the window of a restaurant in San Francisco. Some employers are refusing to consider hiring anyone who doesn't already have a job, leading to increased scrutiny by the EEOC. Justin Sullivan/Getty Images hide caption

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A real estate sign stands outside a home in Las Vegas. Banks are repossessing record numbers of homes in the city, but there's a flip side: It has put homeownership within reach for many low-income buyers. Jae C. Hong/AP hide caption

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