Justin Timberlake presents the Audi A1 at the Geneva Motor Show in Switzerland in 2010. Timberlake stars in a viral marketing campaign for the car company aimed at a younger demographic. Audi's share of the luxury market has risen in recent years. Martin Meissner/AP hide caption

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Professor Anna Stefanopoulou (left) examines a V8 internal combustion engine with students Jacob Larimore and Xinfan Lin at the University of Michigan's Automotive Research Center. The researchers model engine performance to improve efficiency. Courtesy Automotive Research Center hide caption

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Attendees at the Los Angeles Auto Show look at the BMW i8 plug-in hybrid concept car. Toyota's Prius is the best-selling hybrid on the market, but almost every carmaker has some form of hybrid technology. Jae C. Hong/AP hide caption

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A Nissan Leaf charges at a station in Portland, Ore., that can recharge an electric car in 30 minutes. Electric cars could be an integral part of meeting 55-mpg fuel standards by 2025, but many consumers are put off by the vehicles' higher price and what some call "range anxiety." Rick Bowmer/AP hide caption

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Workers put together a Ford Explorer on the assembly line at the automaker's Chicago plant in 2010.

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The new redesigned 2012 Toyota Camry is unveiled during a news event on the Paramount Studios lot in Hollywood, Calif.

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A Hyundai Genesis Coupe is on display in a showroom in Glendale, Calif., last January.

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Detroit Lions Jason Hanson (left) and Don Muhlbach walk off the field after Hanson kicked a 32-yard field goal in overtime to beat the Minnesota Vikings last Sunday in Minneapolis. The Lions won 26-23. Genevieve Ross/AP hide caption

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Ford Crown Victorias sit in a parking lot outside a police station in Chicago. Sales of the Crown Victoria climbed 140 percent in August as police departments stockpiled the popular fleet vehicle before Ford ended its production this week. Scott Olson/Getty Images hide caption

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In a file photo, workers at General Motors' Lordstown Assembly plant in Lordstown, Ohio put the final touches on 2011 Chevrolet Cobalts. The weakening dollar will allow U.S. automakers to export at a financial advantage. Mark Duncan/AP hide caption

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President Obama and congressional leaders work to strike a deal to raise the debt limit at the White House, July 14. Chip Somodevilla/Getty Images hide caption

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Customers walk past a Toyota FJ Cruiser. Toyota brought in 19 percent of African-American buyers, 22 percent of Latino buyers and 33 percent of Asian-American buyers. Yoshikazu Tsuno/Getty Images hide caption

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Although the recession ended two years ago, Americans are still feeling the effects. Consumers are continuing to rely on thrifty measures to push their money further. Chris Hondros/Getty Images hide caption

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People looking for jobs wait in line to speak with potential employers at the Brooklyn Job Fair on April 13 in New York City. Spencer Platt/Getty Images hide caption

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