Republican presidential candidate Mitt Romney participates in a 6th-grade language arts class with Salina Beattie and other students at Universal Bluford Charter School on Thursday in Philadelphia.
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The Deepwater Horizon oil rig burns in the Gulf of Mexico in April 2010. The rig's crew were new to their positions just before the explosion. Such staffing reorganizations are increasingly common as the industry grapples with a staffing shortage.
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