Derby entry El Padrino bites his shank during a bath ahead of the 138th Kentucky Derby this week. Rob Carr/Getty Images hide caption

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U.S. Navy crewmen watch a B-25 bomber take off from the USS Hornet for the Doolittle Raid on Tokyo on April 18, 1942. AP hide caption

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This picture has stayed in Noah Adams' mind. Dr. Kim Sprayberry/Hagyard Equine Medical Institute hide caption

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Sophomore Emily Nugent is among Berea College's 1,600 students who receive free tuition. On average, Berea's students come from families with household incomes of about $25,000. Noah Adams/NPR hide caption

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The Daily Racing Form is the newspaper of the thoroughbred industry. The first one was published in Chicago on Nov. 17, 1894. The Keeneland racetrack in Lexington, Ky., holds a vast collection and is attempting to establish a digital archive.

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Aerial shot of the future site of a Boy Scout camp in West Virginia. Noah Adams/NPR hide caption

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A carbon fiber tobacco moth wing created by Maj. Ryan O'Hara flaps 30 times per second and was photographed using a strobe light. Noah Adams/NPR hide caption

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Wayne Seybold of Marion, Ind., grew up in a trailer park on the factory side of town. As mayor, he's downsized the city's government and expanded the business community. Noah Adams/NPR hide caption

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Portsmouth Public Health Nurse Lisa Roberts helped found the Scioto County Prescription Drug Action Team. Behind her is a memorial to victims of prescription drug abuse. Noah Adams/NPR hide caption

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Educators at the National Museum of the U.S. Air Force teach students about spaceflight. The museum is one of many vying to display a space shuttle. Dan Patterson/National Museum of the U.S. Air Force hide caption

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