Chinese artist Kong Ning walks in her costume made of hundreds of orange plastic blowing horns during her art performance raising awareness of the hazardous smog in front of the Drum tower in a historical part of Beijing on a very polluted day December 7, 2015. Kong, whose works include themes related to China's air pollution problem, named her new performance “The Orange Horns Bride Marries the Blue Sky” and presented it dressed in orange, the colour of the second highest pollution alert level issued again in Beijing as hazardous smog blankets the capital. (Photo by Damir Sagolj/Reuters)

1: Dubai's Burj Khalifa is the tallest building in the world, but perhaps not for long. Saudi Arabia has announced plans to build a 1 kilometer (3,280 foot) tower into the sky, to be named the Jeddah Tower, scheduled for completion in 2020. The Burj Khallifa currently stands at 2,716 ft. (Photo by Matthias Seifert/Reuters)

Team McLaren Mercedes drivers Lewis Hamilton (L) and Jenson Button unveil the new MP-27 Formula 1 car at the McLaren technology centre on February 1, 2012 in Woking, England. (Photo by Mark Thompson/Getty Images)

An enterprising Chinese man pulls a bicycle cart packed high with bags of recyclable plastic containers in Shanghai July 25, 2002. The man sells each kilogram (2.2 pounds) of plastic for 0.08 yuan ($.01) to a nearby depot. (Photo by Claro Cortes IV/Reuters)

People perform during this year's flashmob of silly walks, based on the sketch from the television show Monty Python's Flying Circus by Monty Python troup, in Budapest, Hungary, 01 April 2019. (Photo by Zoltán Balogh/EPA/EFE)

Models present creations from the SGM ART MOUSE JI during the China Fashion Week in Beijing, China, 25 October 2020. The fashion​ event runs from 24 October to 01 November. (Photo by Wu Hong/EPA/EFE)

Models wait backstage ahead of their presentation of creations from the YINMU collection by designer Wei Jiang during the China Fashion Week in Beijing, China, 26 October 2020. The fashion event runs from 24 October to 01 November 2020. (Photo by Wu Hong/EPA/EFE)

Musician Jerome Gamble plays guitar to accompany the recorded music as it is played to the city below on September 01, 2020 in Bristol, England. Created by Bristol-based artist Luke Jerram and composer Dan Jones, “Sky Orchestra – A Moment in Time” was first performed at the Bristol International Balloon Fiesta in 2003. (Photo by Finnbarr Webster/Getty Images)