Tank crew standing in front of M-4 tank, Ft. Knox, Kentucky, June, 1942. (Alfred Palmer/OWI/LOC)

Members of the Women's Fire Brigade with their Chief Officer, March 1916. (Photo by Topical Press Agency)

A Ukrainian serviceman is seen at his position on the front line in Krasnogorivka near Donetsk, Ukraine, August 12, 2016. (Photo by Gleb Garanich/Reuters)

A Shiite fighter from the Hashed al-Shaabi (Popular Mobilisation) patrols in the village of Ayn Nasir, south of Mosul, on October 29, 2016, after recapturing it from Islamic State group jihadists in an ongoing operation to retake the city of Mosul. Iraqi paramilitary forces launched an operation to cut the Islamic State group's supply lines between its Mosul bastion and neighbouring Syria, opening a new front in the nearly two-week-old offensive. (Photo by Ahmad Al-Rubaye/AFP Photo)

Birds made of recycled tires are displayed in a shop located on the Panamerican highway near Catarina town, May 7, 2015. Salazar recycles used tyres to make bird figurines and sofas to sell in his shop located on the Panamerican highway. (Photo by Oswaldo Rivas/Reuters)

Anti-government protesters take cover during clashes with security forces who are firing tear gas from La Carlota airbase in Caracas, Venezuela, Wednesday, May 1, 2019. Opposition leader Juan Guaidó called for Venezuelans to fill streets around the country Wednesday to demand President Nicolás Maduro's ouster. Maduro is also calling for his supporters to rally. (Photo by Ariana Cubillos/AP Photo)

Colombia midfielder Natalia Gaitan (3) goes up for a header against Mexico midfielder Nayeli Rangel (7) in Moncton, June 9, 2015. (Photo by Matt Kryger/USA TODAY Sports)

A marine aims an RPG-7, a portable rocket- propelled grenade launcher, during military exercises conducted by the Russian Pacific Fleet' s naval infantry unit at the Bamburovo firing range on February 2, 2017. The drills are a part of preparations for the Suvorov Attack and Sniper Line army competitions. (Photo by Yuri Smityuk/TASS)