Russia' s Tiffani Zagorski and Russia' s Jonathan Guerreiro compete in the ice dance free dance of the figure skating event during the Pyeongchang 2018 Winter Olympic Games at the Gangneung Ice Arena in Gangneung on February 20, 2018. (Photo by Lucy Nicholson/Reuters)

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)

A reveller poses for a photo during the LGBT Pride Parade in Copacabana beach in Rio de Janeiro, Brazil, November 15, 2015. (Photo by Pilar Olivares/Reuters)

A U.S. Army B-24 Liberator Bomber is hailed by a ground crewman as it takes off over a line of shark- nosed fighter planes at an advanced base in China on a mission on October 10, 1943, to bomb Japanese installations. (Photo by AP Photo)

Skeleton involves a person riding a small sled down a frozen track while lying face down. The sport is a more intense form of luge because skeleton competitors leap onto the sled and slide downhill head first. Skeleton athletes can reach up to 80 mph on straightaways, causing forces up to 5g, so the helmet is a critical component for attitude as well as safety.

Japan' s Kaori Sakamoto competes in the women' s single skating short program of the figure skating event during the Pyeongchang 2018 Winter Olympic Games at the Gangneung Ice Arena in Gangneung on February 21, 2018. (Photo by John Sibley/Reuters)

A teenage girl from the Santa Marta favela slum puts on a pair of high heels for a group debutante ball organized by the Pacifying Police Unit from her neighborhood in Rio de Janeiro, Brazil, Friday, August 29, 2014. The ball, which relied on volunteers who coiffed and made up the girls and a formal wear shop that loaned the dresses, helped build goodwill between pacified favelas' residents and the officers who patrol them. (Photo by Silvia Izquierdo/AP Photo via The Palm Beach Post)

In this January 11, 2017 photo, Erika Martins uses black electrical tape to create a customer's bikini, in order to attain crisp tan lines, on her rooftop Erika Bronze salon in the suburb of Realengo in Rio de Janeiro, Brazil. Martins wears a microphone connected to an open speaker system in order to direct her assistants to clients who need more tanning lotion or a sprinkling of water on their skin. (Photo by Renata Brito/AP Photo)