Ng Sin Nee (L) and Lee Shin May (R) from Malaysia take pictures with the panoramic view of the city from the Sky Box at KL Tower, the world's seventh tallest telecommunications tower, in Kuala Lumpur on May 24, 2016. Officially opened on May 20, the Sky Box has been the latest attraction for tourists arriving to the Malaysian capital. It stands 300 metres above ground and can fit six people at any one time, and offers spectacular views of the Kuala Lumpur skyline, including the iconic Petronas Twin Towers. (Photo by Mohd Rasfan/AFP Photo)

Artist Kong Ning wears a wedding dress made from respirators to highlight concerns about air quality and pollution in Beijing, China on December 1, 2015. (Photo by Luo Xiaoguang/Xinhua Press/Corbis)

A prototype battery-powered plane, called Greased Lightning or GL-10 is pictured flying at NASA's Langley Research Center in this undated handout photo obtained by Reuters May 1, 2015. The plane, which has 10 engines and can take off like a helicopter and fly efficiently like an aircraft, is currently in the design and testing phase. (Photo by Reuters/NASA)

Riot police arrest an anti-government protester in Ouagadougou, capital of Burkina Faso, October 30, 2014. Thousands of protesters marched on Burkina Faso's presidential palace after burning the parliament building and ransacking state television offices on Thursday, forcing President Blaise Compaore to scrap a plan to extend his 27-year rule. Emergency services said at least three protesters were shot dead and several others wounded by security forces when the crowd tried to storm the home of Compaore's brother. Security forces also fired live rounds and tear gas at protesters near the presidency in the Ouaga 2000 neighborhood. (Photo by Joe Penney/Reuters)

A Snowboarder participates in a waterslide contest, which consists of gliding over a water pool embedded in snow, during the closing event of the ski resort of Nendaz, southwestern Switzerland, Monday, April 21, 2014. (Photo by Maxime Schmid/AP Photo/Keystone)

A South Sudanese model applies make-up during the Festival of Fashion and Arts for Peace in Juba August 9, 2014. (Photo by Andreea Campeanu/Reuters)

This picture taken on September 3, 2014 shows a man taking pictures of floodwater released from the Three Gorges Dam, a gigantic hydropower project on the Yangtze river, in Yichang, central China's Hubei province, after heavy downpours in the upper reaches of the dam caused the highest flood peak of the year. Eleven people died and 27 others are missing after torrential rains battered southwest China's Chongqing, a municipality in the upper reaches of the Three Gorges Dam, causing thousands of houses to collapse, state media said. (Photo by AFP Photo/Stringer)

A woman takes a photograph of a sculpture titled “Couple Under an Umbrella, 2013” by Australian sculptor Ron Mueck during a preview of his exhibition at the Pinacoteca Museum in Sao Paulo November 19, 2014. (Photo by Nacho Doce/Reuters)