New York City policemen tangled with demonstrators at a subway station on the opening day of the New York World's Fair, April 22, 1964. Youths attempted to stall the train, which was headed from the city to the fairgrounds, as a form of protest on behalf of civil rights for blacks. (Photo by Charles Gorry/AP Photo)

The players of Denmark huddle prior to the FIFA Women's World Cup qualifier match between Denmark and Sweden at Viborg Stadion on September 4, 2018 in Viborg, Denmark. (Photo by Lars Ronbog/FrontZoneSport via Getty Images)

The Hot air balloon is flying at the Warsteiner International Hot Air Balloon Show in the Arnsberger Forest National Park on September 2, 2011 near Warstein, Germany. Approximately 200 hot air balloons are scheduled to take part in the nine-day event sponsored by the Warsteiner brewery. (Photo by Mathis Wienand/Getty Images)

A pilot inflates his balloon before the 37th International Hot Air Balloon Week in Chateau-d'Oex, January 24, 2015. According to the organizers, over 80 balloons from 20 countries are participating in the ballooning event in the Swiss mountain resort. (Photo by Pierre Albouy/Reuters)

Francisco da Silva Vale, 61, cools off fish with ice produced on solar-powered ice machines at Vila Nova do Amana community in the Sustainable Development Reserve, in Amazonas state, Brazil, September 23, 2015. Three solar-powered machines, are producing about ninety kilos of ice per day, in a region with poor access to electric energy, which used to be produced only with diesel oil, in the Amazon rain forest. (Photo by Bruno Kelly/Reuters)

A grizzly bear eats a frozen fruits during a hot summer day at Rio de Janeiro's zoo January 13, 2015. According to a local climate institute, temperatures in Rio de Janeiro on Tuesday rose up to 34 degrees Celsius (93.2 degrees Fahrenheit). (Photo by Sergio Moraes/Reuters)

Visitors play in front of hot air balloons during the 2016 International Hot Air Balloon Festival in Taitung, southeast of Taiwan, 01 July 2016. Thirty-one hot-air balloon teams from 14 countries join the six days of competition during the festival, which will run from 01 July to 07 August 2016. (Photo by Ritchie B. Tongo/EPA)