Coursera founders Andrew Ng and Daphne Koller are computer science professors at Stanford University. Jeff Chiu/AP hide caption

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President Obama speaks during a campaign event at University of Colorado Boulder Sept. 2. He and his Republican challenger, Mitt Romney, will have their first debate at the University of Denver on Wednesday. Pablo Martinez Monsivais/AP hide caption

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President Barack Obama and Republican presidential candidate Mitt Romney both campaigned in the battleground state of Ohio this week. AP hide caption

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New York Times publisher Arthur Ochs Sulzberger in his office in 1973. Anthony Camerano/AP hide caption

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Mia Love, the mayor of Saratoga Springs, Utah, addresses the Republican National Convention in Tampa, Fla., on Aug. 28. She's running for Congress against incumbent Democrat Jim Matheson. J. Scott Applewhite/AP hide caption

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County Sheriff Lee Baca faces what may be the toughest fight of his 14-year political career. Damian Dovarganes/AP hide caption

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First-grade teacher Euginia Miller reads to her class at Avondale Elementary School in Birmingham, Ala. In this crucible of the civil rights movement, the city's schools are being reintegrated, as a handful of middle-class parents ignore the school district's poor reputation and enroll their kids in the city's public schools. Dan Carsen/WBHM hide caption

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In Roseville, Mich., officials carry away a soil sample taken from under a driveway where a tipster says a body was buried decades ago — raising speculation that it might be Jimmy Hoffa. Bill Pugliano/Getty Images hide caption

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