Students stand on the roof of a wooden boat as haze blankets the Musi River while they travel to school in Palembang, on Indonesia's Sumatra island, September 10, 2015. Indonesia is investigating 10 firms over worsening forest fires that have created a blanket of smog over Southeast Asia, threatening them with sanctions if they are found responsible, a government minister said on Tuesday. The thick haze from Indonesia's Sumatra and Kalimantan islands has forced the repeated cancellation of flights in the area and pushed air quality to unhealthy levels in neighbouring Singapore and Malaysia. (Photo by Reuters/Beawiharta)

A student gets off a police vehicle which carried her to a high school to arrive in time for a college entrance exam in Seoul, South Korea, Thursday, November 18, 2021. About 510,000 high school seniors and graduates across the country are expected to take the College Scholastic Ability Test. (Photo by Ahn Young-joon/AP Photo)

High school seniors clad in traditional attire bow during a joint graduation and coming-of-age ceremony at Dongmyung Girls' High School in Seoul South Korea, Tuesday, February 7, 2023. (Photo by Ahn Young-joon/AP Photo)

This aerial photo taken on March 2, 2023 shows bulldozers working to build high-standard farmlands in Pucheng County, southeast China's Fujian Province. A new round of high-standard farmlands building is underway in Pucheng County in preparation of spring ploughing. (Photo by Xinhua News Agency/Rex Features/Shutterstock)

Venezuela: An anti-government protester wearing a Guy Fawkes mask throws a molotov cocktail at the Bolivarian National Police during clashes in Caracas, Venezuela, Thursday, April 17, 2014. Opposition protesters have been demonstrating against high crime, high inflation and shortages of basic goods since mid-February. (Photo by Ramon Espinosa/AP Photo)

Fans bath in the mud during the “Woodstock Festival Poland” on August 3, 2017 in Kostrzyn Nad Odra, Poland. The annual 3 day music festival organised by The Great Orchestra of Christmas Charity, one of Polands most respected charities aims at spreading awareness about drugs and violence. Przystanek Woodstock in Poland is the largest Europe open air festival. (Photo by Music/Alamy Stock Photo)

Tracy Sarita celebrates the sunrise during the Burning Man 2015 “Carnival of Mirrors” arts and music festival in the Black Rock Desert of Nevada, September 3, 2015. Approximately 70,000 people from all over the world are gathering at the sold-out festival to spend a week in the remote desert to experience art, music and the unique community that develops. (Photo by Jim Urquhart/Reuters)

Bibi rides her bike on the Playa during the Burning Man 2015 “Carnival of Mirrors” arts and music festival in the Black Rock Desert of Nevada, August 31, 2015. Approximately 70,000 people from all over the world are gathering at the sold-out festival to spend a week in the remote desert to experience art, music and the unique community that develops. (Photo by Jim Urquhart/Reuters)