Student protestors, including one girl with a camera, struggle with soldiers from the Chinese Army, the PLA. Tiananmen Square, 1989. (Photo by Jeff Widener/Associated Press)

A man holds up for a picture a one hundred trillion Zimbabwean dollars note inside a shop in Harare, Zimbawe, June 12, 2015. Hyperinflation in Zimbabwe was a period of currency instability that began in the late 1990s shortly after the confiscation of private farms from landowners, towards the end of Zimbabwean involvement in the Second Congo War. During the height of inflation from 2008 to 2009, it was difficult to measure Zimbabwe's hyperinflation because the government of Zimbabwe stopped filing official inflation statistics. However, Zimbabwe's peak month of inflation is estimated at 79.6 billion percent in mid-November 2008. (Photo by Philimon Bulawayo/Reuters)

Pigeons fly out from the mouth of a giant Buddha statue at Wat Nam Daeng Buddhist temple in Chachoengsao province, east of the Thai capital Bangkok, on October 11, 2020. (Photo by Mladen Antonov/AFP Photo)

Then U.S. Army First Lieutenant Kirsten Griest (C) and fellow soldiers participate in combatives training during the Ranger Course on Fort Benning, Georgia, in this handout photograph taken on April 20, 2015 and obtained on August 20, 2015. When Griest and another woman completed the daunting U.S. Army Ranger school this week they helped end questions about whether women can serve as combat leaders, as the Pentagon is poised to open new roles, including elite Navy SEALs, to women in coming months. The feat by Griest and First Lieutenant Shaye Haver followed a re-evaluation of the role of women after their frontline involvement in Iraq and Afghanistan and the end of a rule barring them from combat roles in 2013. (Photo by Spc. Nikayla Shodeen/Reuters/U.S. Army)

A stuntman performs in a car at the “Well of Death” at an exhibition in Srinagar, India, Friday, May 23, 2014. In the Well of Death, stunt drivers on motorbikes and cars drive in circles around the vertical walls of the well-shaped construction. (Photo by Dar Yasin/AP Photo)

A fighter jet flies above as Ukrainian soldiers sit on an armoured personnel carrier in Kramatorsk, in eastern Ukraine April 16, 2014. Ukrainian government forces and separatist pro-Russian militia staged rival shows of force in eastern Ukraine on Wednesday amid escalating rhetoric on the eve of crucial four-power talks in Geneva on the former Soviet country's future. (Photo by Marko Djurica/Reuters)

An American flag flutters on a young tree stripped of bark after a massive tornado passed through the town killing at least 116 people May 24, 2011 in Joplin, Missouri. The tornado that ripped through the town of about 50,000 people May 22, is being called the deadliest single tornado in the U.S. in 60 years. (Photo by Julie Denesha/Getty Images)

Technical staff take shelter as a helicopter takes off prior to the Nendaz Freeride skiing and snowboard competition, a Freeride World Tour Qualifier (FWQ) event, on the Mont Gond in Nendaz, Switzerland on March 21, 2018. (Photo by Valentin Flauraud/EPA/EFE/Rex Features/Shutterstock)