160707-N-TC720-231 MEDITERRANEAN SEA (July 7, 2016) Chief Gunner's Mate Alvin Johnson, from Lubbock, Texas, left, watches Gunner's Mate Seaman Benjamin Dixon, from Norfolk, Virginia, fire a 25mm machine gun aboard USS Donald Cook (DDG 75) during live fire gunnery exercises July 7, 2016. Donald Cook, an Arleigh Burke-class guided-missile destroyer, forward deployed to Rota, Spain is conducting a routine patrol in the U.S. 6th Fleet area of operations in support of U.S. national security interests in Europe. (U.S. Navy photo by Mass Communication Specialist 2nd Class Mat Murch/Released)