Planes land in fog at Heathrow Airport, west London, as heavy fog covers a many parts of the south east, on April 1, 2014. (Photo by Steve Parsons/PA Wire)

Young gymnasts practice pull-up on a bar at a gymnasium of a sports school in Jiaxing, Zhejiang province April 11, 2015. (Photo by William Hong/Reuters)

Russian Police academy female cadets march during a rehearsal for the Victory Day military parade at Dvortsovaya (Palace) Square in St Petersburg, Russia, Wednesday, May 7, 2014. Victory Day, marking the defeat of Nazi Germany, is Russia's most important secular holiday celebrated on May 9. (Photo by Dmitry Lovetsky/AP Photo)

An Oakland Raiders cheerleader performs during an NFL preseason football game against the Detroit Lions in Oakland, Calif., Friday, August 15, 2014. (Photo by Marcio Jose Sanchez/AP Photo)

Health authority workers sanitise the rural community of Teocelo, Veracruz, Mexico on May 12, 2020 – in the hope of preventing the spread of COVID-19 infections. (Photo by Hector Adolfo Quintanar Perez/ZUMA Wire/Rex Features/Shutterstock)

Britain Football Soccer, Burnley vs Swansea City, Premier League, Turf Moor on August 13, 2016. Burnley fan with face paint outside the stadium before the match. (Photo by Ed Sykes/Reuters/Action Images/Livepic)

A saddle-billed stork stands in the grassland at the Nairobi National Park near Nairobi, Kenya January 23, 2017. (Photo by Thomas Mukoya/Reuters)

To the woman presented a flower in Sevastopol, Ukraine, on March 8, 2013. Activists presented this day on the street free 155 tulips to women. The police tried to arrest activists for illegal trade as couldn't believe in free distribution of flowers. (Photo by Sergey Anashkevitch)