Slideshow: Race Against Time

Fire boat response crews battle the blazing remnants of the off shore oil rig Deepwater Horizon, off Louisiana, in this handout photograph taken on April 21, 2010 and obtained on April 22. The oil drilling rig that had burned for 36 hours in the Gulf of Mexico sank Thursday, April 22nd as hopes dimmed for 11 missing workers and the risk of a major oil spill loomed, officials said. (REUTERS/Ho New) Related Video: Gulf Oil Spill: Up Close