Promotional models use their smartphones during their break at the Global Mobile Internet Conference in Beijing May 6, 2014. Mobile Internet industry executives, developers and investors from more than 30 countries took part in the Global Mobile Internet Conference in Beijing, the organiser said. (Photo by Kim Kyung-Hoon/Reuters)

Soldiers of China's People's Liberation Army (PLA) jump as part of their winter training in temperature of negative 26 degrees Celsius at China's border with Russia in Heihe, Heilongjiang province, December 14, 2015. (Photo by Reuters/Stringer)

The television tower is pictured in Berlin, Germany, May 29, 2016. (Photo by Hannibal Hanschke/Reuters)

An F-18 Hornet fighter jet on May 27, 2025 lands and takes off from a highway during Baana 25, a military exercise held by the Finnish air force. (Photo by The Times)

The world heavyweight boxing champion Joe Frazier, before his fight with Joe Bugner. (Photo by Evening Standard/Getty Images). 18th June 1973

Sally Fitzgibbons of Australia competes in the Women's Final of the 2012 Australian Surfing Open on February 19, 2012 in Manly, Australia. (Photo by Cameron Spencer/Getty Images)

A man is silhouetted as he stands on a walkway in the sky lobby at the Chancellery, the seat of German Chancellor Angela Merkel (not pictured) in Berlin, May 7, 2014. (Photo by Thomas Peter/Reuters)

A man dressed in red-white-and-blue sits on the curb during a protest against President-elect Donald Trump, Wednesday, November 9, 2016, in Seattle's Capitol Hill neighborhood. (Photo by Ted S. Warren/AP Photo)