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A selection of mobile apps relating to the COVID-19 coronavirus pandemic are seen on a tablet screen on March 26, 2020 in London, England. The Coronavirus (COVID-19) pandemic has spread to many countries across the world, claiming over 20,000 lives and in

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America flags are presented for the send of the U.S. Navy hospital ship USNS Comfort at Naval Air Station Norfolk Pier 8, Saturday, March 28, 2020, as she gets underway for New York City where she will support the city’s response to COVID-19.

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Commuters wear protective masks as they exit a train at a subway station during Monday rush hour on April 13, 2020 in Beijing, China

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Sri Lankan officials inspect St. Sebastian's Church in Negombo, north of Colombo, after multiple explosions targeting churches and hotels across Sri Lanka on April 21, 2019, in Negombo, Sri Lanka.

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Preston Dunlap, Air Force Chief Architect, briefs Department of Defense senior leaders on the planned core system for JADC2ABMS

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DARPA completed its Anti-Submarine Warfare Continuous Trail Unmanned Vessel program and then transferred the technology demonstration vessel, christened Sea Hunter, to the Office of Naval Research.

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Tedros Adhanom, Director General of the World Health Organization, (L) shakes hands with Chinese President Xi Jinping before a meeting at the Great Hall of the People, on January 28, 2020 in Beijing, China.