Students from CAS Ballet Theatre School stretch on the sidewalk Saturday, February 20, 2016, in Ann Arbor, Mich. (Photo by Junfu Han/The Ann Arbor News via AP Photo)

In this April 28, 2014 file photo, a woman throws a rock and a bag at police blocking her from getting home in the Huepetuhe district of the Madre de Dios region of Peru. Security forces began destroying illegal gold mining machinery in Peru's southeastern jungle region of Madre de Dios, as authorities began enforcing a ban on illegal mining. (Photo by Rodrigo Abd/AP Photo)

Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)

Bride Yulia Tagil sits on the backseat of a bike as she arrives for her alternative wedding ceremony on a square in Tel Aviv July 25, 2010. The alternative wedding ceremony was intended to demonstrate against the current situation in Israel, where the only way for Jews to get married by law is through the Chief Rabbinate. (Photo by Nir Elias/Reuters)

Women sunbath as Ferrari's Brazilian driver Felipe Massa drives past during the third practice session at the Circuit de Monaco in Monte Carlo on May 25, 2013 ahead of the Monaco Formula One Grand Prix. (Photo by Alexander Klein/AFP Photo)

Robert Price of TREWGrip LLC demonstrates a TREWGrip handheld rear-type keyboard and air mouse for Apple and Android tablets at the “CES: Unveiled”, media preview for International CES, at the Mandalay Bay Convention Center in Las Vegas on January 5, 2014. (Photo by Robyn Beck/AFP Photo)

“Horst Faas (28 April 1933 – 10 May 2012) was a German photo-journalist and two-time Pulitzer Prize winner. He is best-known for his images of the Vietnam War”. – Wikipedia

Photo: A U.S. crewman runs from a crashed CH-21 Shawnee troop helicopter near the village of Ca Mau in the southern tip of South Vietnam, December 11, 1962. Two helicopters crashed without serious injuries during a government raid on the Viet Cong-infiltrated area. Both helicopters were destroyed to keep them out of enemy hands. (Photo by AP Photo/Horst Faas)

A dead body is seen on the ground after violence erupted in the Independence Square in Kiev February 20, 2014. Ukrainian protesters seized back Kiev's Independence Square in fresh clashes with riot police on Thursday that left several injured and possibly two demonstrators dead. (Photo by David Mdzinarishvili/Reuters)