In Dallas, compressed natural gas (CNG) cabs get to cut in front of regular gas cabs at the Love Field Airport pick-up line. Justin Sullivan/Getty Images hide caption

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Omar Sharriff performs in Marshall, Texas in December 2010. Ron Munden/EastTexasTowns.com hide caption

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Cornelius Dupree Jr. raises his hand to testify Tuesday while attorney Barry Scheck looks on. Dupree served 30 years in connection with a rape and robbery before being exonerated by DNA evidence. Mike Fuentes/AP hide caption

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Lumar C. LeBlanc was photographed for the Surviving Katrina and Rita in Houston project installation, "Who We Are." LeBlanc was interviewed by Dallas McNamara, a fellow Katrina evacuee, on Jan. 21, 2007. Dallas McNamara hide caption

itoggle caption Dallas McNamara

Mary Gallagher, photographed at her home in October 2007, the year after her husband, Marine Gunnery Sgt. James Gallagher, took his own life. Tina Fineberg/AP hide caption

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Oil burns at the Ixtoc 1 offshore drilling rig in December 1979. The rig dumped 140 million gallons of crude oil into the Gulf of Mexico and covered about 170 miles of the South Texas coast, including Galveston. John Hoagland/Liaison/Getty Images hide caption

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Carl Main of Caddo Gap, Ark., removes flood debris from a pile near Langley, Ark., Sunday. Search and recovery efforts continue after flooding swept through a nearby campground early Friday, killing at least 19 people. Authorities believe just one, 8-year-old Jadyn Basinger, remains missing. Sue Ogrocki/AP hide caption

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A cluster of Bill Halter and Blanche Lincoln campaign signs at an intersection in Little Rock, Ark., on Tuesday. Danny Johnston/AP hide caption

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A view of the wreckage at the BP facility in Texas City, south of Houston, a day after the explosion on March 23, 2005. William Philpott/AFP/Getty Images hide caption

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Two ships float near the massive oil slick spreading in the Gulf of Mexico after a drilling rig sank last week off the coast of Louisiana. The slick is 80 miles long and 40 miles wide and growing. Brendan Farrington/AP hide caption

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