In this photo taken Wednesday, Oct. 15, 2014, Ryan Billing, a development engineer for the University of California, Davis, operates the controls of the Yamaha RMax unmanned helicopter during a demonstration of its aerial application capabilities at the University of California, Davis’ Oakville Station test vineyard in Oakville, Calif. Researchers at UC Davis have been studying the effectiveness of the drone’s ability for spraying pest control and nutritional materials on the test vineyard in California’s Napa Valley. (AP Photo/Rich Pedroncelli)
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