A woman affected by tear gas is assisted during a May Day protest against austerity measures, in San Juan, Puerto Rico May 1, 2018. (Photo by Alvin Baez/Reuters)

Rice seedling festival is a traditional folk festival in longji, guangxi, China on June 9, 2019, during grain in ear season. (Photo by Costfoto/Barcroft Media)

A Spanish national police officer uses his club to hit a protester during a demonstration called the Catalan pro-independence left youth group “Arran” on October 19, 2019 in Barcelona, a day after nearly 200 people were hurt in another night of violent clashes in Catalonia. The deterioration came on the fifth consecutive day of protests in the Catalan capital and elsewhere over a Spanish court's jailing of nine separatist leaders on sedition charges over a failed independence bid two years ago. (Photo by Josep Lago/AFP Photo)

Number 10. BELL H-13 SIOUX was a two-bladed, single engine, light helicopter built by Bell Helicopter. Westland Aircraft manufactured the Sioux under license for the British military as the Sioux AH.1 and HT. In 1947, the United States Air Force ordered the improved Bell Model 47A. Most were designated YR-13 and three winterized versions were designated YR-13A. The United States Army first ordered Bell 47s in 1948 under the designation H-13. These would later receive the name Sioux. The Bell-built H-13 B is seen airborne in this April 29, 1951 photo. The helicopter is equipped with a 173 horsepower engine, cruises at 85 miles per hour, climbs 900 feet in a minute and has a service ceiling of 11,500 feet. (Photo by AP Photo)

People protest for greater action against climate change during the People's Climate March on September 21, 2014 in New York City. The march, which calls for drastic political and economic changes to slow global warming, has been organized by a coalition of unions, activists, politicians and scientists. (Photo by Andrew Burton/Getty Images)

A protester gestures after he saw a dead protester in Kampala, Uganda February 15, 2016. At least one person has been killed in Uganda's capital Kampala as police clashed with opposition supporters after briefly detaining a top presidential candidate twice as he tried to hold campaign rallies days before a general election. Several people were wounded in the clashes as police fired bullets and tear gas while opposition supporters hurled rocks and erected street barricades in the capital's Wandegeya suburb, witnesses said according to a Reuters news agency report. (Photo by Goran Tomasevic/Reuters)

Show promoters for Motolite batteries sit on a jeepney as they pose for photographers during the Manila International Auto show in Pasay, Metro Manila, Philippines on April 4, 2013. (Photo by Erik De Castro/Reuters)