Brett Throckmorten of Barnes Bullets shows Logan Wingo how to sight down an electronic rifle in the trade booth area during the National Rifle Association's annual meeting in Nashville, Tennessee, April 11, 2015. (Photo by Harrison McClary/Reuters)

A protester jumps on the table in front of the European Central Bank President Mario Draghi during a news conference in Frankfurt, April 15, 2015. The news conference was disrupted on Wednesday when a woman in a black T-shirt jumped on the podium. (Photo by Kai Pfaffenbach/Reuters)

A boy carries empty sacks after bringing different types of plastic materials to a recycling station in Khartoum North April 16, 2015. People bring bottles and other plastic materials to the station for recycling, and get paid in return. (Photo by Mohamed Nureldin Abdallah/Reuters)

Some women doing yoga pose on the hammocks during the Anti-Gravity yoga class at Svarga e-Motion Sanctuary at Dharmawangsa Square, Jakarta, Saturday, April 18, 2015. Anti-Gravity Yoga or “aerial yoga”, is a new type of yoga, originating in New York but now being practised in several countries, which combines the traditional yoga poses, pilates and dance with the use of a hammock. (Photo by Jurnasyanto Sukarno/JG Photo)

A girl looks out from the window of a “La Sabana” tourist train in La Caro March 1, 2015. The “La Sabana” tourist train that runs through the capital was founded by Eduardo Rodriguez, a railway engineer. Rodriguez has worked on Colombia's railway system his whole life and now, with an air of nostalgia, transports thousands of tourists in renovated steam locomotives that he fixes in Bogota's Central Station which dates back to 1913. (Photo by Jose Miguel Gomez/Reuters)

Lenka Tanner is pictured in Nottingham, United Kingdom on March 11, 2015. She starred in the Kuoni advert, Run on Water, advertising luxury holidays. She has set up her own synchronised swimming team called AquaStars. Tanner was born in Slovakia and starting synchronised swimming at the age of six. (Photo by Lucy Ray/The Guardian)

This photo provided by Joan Marcus on August 28, 2015 shows ballerina Misty Copeland in the musical “On the Town” at the Lyric Theatre in New York. Until September 6, 2015 Copeland will play Miss Turnstiles, a love interest for one of three sailors enjoying a few hours of shore leave in 1940s New York. (Photo by Joan Marcus via AP Photo)

The Soyuz TMA-18M spacecraft is transported from an assembling hangar to its launch pad at the Baikonur cosmodrome, Kazakhstan, August 31, 2015. The Soyuz is scheduled to blast off with Aidyn Aimbetov of Kazakhstan, Sergei Volkov of Russia and Andreas Mogensen of Denmark to the International Space Station (ISS) on September 2, 2015. (Photo by Shamil Zhumatov/Reuters)