People walk in the storm surge from Hurricane Isaac along Lake Pontchartrain in New Orleans. Isaac was later downgraded to a tropical storm as it continued to grind its way through the Gulf Coast, dropping torrential rain and generating dangerous storm surges. Gerald Herbert/AP hide caption

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Rescue workers transport residents trapped by rising water from Hurricane Isaac in the River Forest subdivision on Wednesday in LaPlace, Louisiana. The large Level 1 hurricane slowly moved across southeast Louisiana, dumping huge amounts of rain and knocking out power across the Gulf Coast. Chris Graythen/Getty Images hide caption

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Can you recognize the top five logical fallacies lobbed so far in this year's presidential campaign? spxChrome/iStockphoto.com hide caption

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Mike Stuart of Dynamic Aviation speaks to the media this week about the type of plane used for aerial spraying in Dallas. The city and county are conducting aerial spraying to combat the nation's worst outbreak of West Nile virus, which has killed at least 10 people and sickened about 200. LM Otero/AP hide caption

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Apollo 17 commander Eugene A. Cernan takes a Lunar Roving Vehicle for a spin at the Taurus-Littrow landing site during the 1972 mission. Harrison H. Schmitt/NASA hide caption

itoggle caption Harrison H. Schmitt/NASA

Members of the Milwaukee-area Sikh community gather Monday in Oak Creek, Wis., to learn more information about a shooting spree that left six people dead. Sikhs have faced a number of attacks in the U.S. in recent years. Scott Olson/Getty Images hide caption

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