Janet Yellen smiles as President Obama announces her nomination for Federal Reserve chairwoman on Oct. 9. Jewel Samad/AFP/Getty Images hide caption

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The small streets of Williston, N.D., are bustling with trucks early in the morning. Annie Flanagan for NPR hide caption

itoggle caption Annie Flanagan for NPR

SpaceX's Dragon spacecraft atop rocket Falcon 9 lifts off from Cape Canaveral in Florida in May 2012. The launch made SpaceX the first commercial company to send a spacecraft to the International Space Station. Roberto Gonzalez/Getty Images hide caption

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FedEx employees sorted through mounds of packages in December at one of the company's facilities in Miami. Consumer spending helped fuel the economy in the third quarter. Gross domestic product grew at a 3.2 percent annual rate (a figure that adjusts for holiday spending to show the "real" growth). Joe Raedle/Getty Images hide caption

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Cameron (left) and Tyler Winklevoss testified Wednesday at a hearing about virtual currencies held by the New York Department of Financial Services. Craig Ruttle/AP hide caption

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Gas flaring near Highway 85 southwest of Williston. Analysts estimate that almost 30 percent of the gas being produced in the state is burned off. Jeff Brady/NPR hide caption

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