An instructor guides a student from the General Yermolov Cadet School as she aims with a gun during a field exercise outside the south Russian city of Stavropol January 24, 2015. The General Yermolov Cadet School in Stavropol is a state-run institution that teaches military and patriotic classes in addition to a normal syllabus. (Photo by Eduard Korniyenko/Reuters)

In this undated handout photograph from the “Inside Out Project”, a poster bearing the image of a Pakistani girl whose parents, lawyers say, were killed in a drone strike, lies in a field at an undisclosed location in the northwestern Khyber-Pakhtunkhwa province. A group of artists in Pakistan are hoping to generate “empathy” among US drone operators by placing giant posters of children in the country's troubled tribal regions. (Photo by AFP Photo)

The “Escape Velocity” moving sculpture by artist group Poetic Kinetics looms over Coachella festivalgoers on the Empire Polo Field, on the first day of the 2014 Coachella Music and Arts Festival in Indio, California, on April 11, 2014. (Photo by Chris Pizzello/Invision)

A student from the General Yermolov Cadet School takes part in weapons training during a two-day field exercise near the village of Sengileyevskoye, just outside the south Russian city of Stavropol April 13, 2014. The General Yermolov Cadet School in the southern Russian city of Stavropol is a state-run institution that teaches military and patriotic classes in addition to a normal syllabus. (Photo by Eduard Korniyenko/Reuters)

An Israeli soldier looks through her cell phone as she enjoys the Ranunculus flowers in a field in the southern Israeli Kibbutz of Nir Yitzhak, located along the Israeli- Gaza Strip border, during the Jewish holiday of Pesach (Passover) on April 12, 2017. (Photo by Menahem Kahana/AFP Photo)

Santa Jerry Julian of Colorado Springs, Colorado hides in the grass following a ride on the Polar Express during a field trip from the Charles W. Howard Santa Claus School in Midland, Michigan, U.S. October 28, 2016. (Photo by Christinne Muschi/Reuters)

In this Thursday, May 31, 2018 photo, a temporary worker using a lantern collects white asparagus from a field in Caparroso, around 85 km (52 miles) from Pamplona, northern Spain. Dubbed the “white gold” of these northern Spanish farms because of their color and the high price they fetch in markets and restaurants around the world, the stringy delicacy is planted every fall and picked each year between April and June, at the height of the spring. (Photo by Alvaro Barrientos/AP Photo)

Wild elephants, including a tusker (C), rummage through garbage dumped at an open ground in the village of Digampathana in north- central Sri Lanka on August 19, 2017. Sri Lanka has banned the dumping of garbage at open fields and near wildlife reserves, but the practice continues. (Photo by Lakruwan Wanniarachchi/AFP Photo)