National Guardsmen are put through riot training in Boston's Commonwealth Armory on Friday, October 18, 1974. Massachusetts Gov. Francis W. Sargent called up the guard to quell school violence, but the city has been relatively calm and the guard has remained in the armories. (Photo by JWG/AP Photo)

A boy looks inside the skull of a Tyrannosaurus Rex replica at the Egidio Feruglio Museum in Trelew, Argentina, in this May 18, 2014 file photograph. Scientists on July 28, 2015 unveiled a comprehensive analysis of the teeth of the group of carnivorous dinosaurs called theropods, which include the Tyrannosaurus Rex, detailing a unique serrated structure that let them chomp efficiently through the flesh and bones of large prey. (Photo by Maxi Jonas/Reuters)

A red fox sits in front of a Eurofighter Typhoon combat jet on the grounds of the 2014 ILA Berlin Air Show, in Selchow near Schoenefeld, Germany, Thursday, May 15, 2014. The International Aviation and Aerospace Exhibition ILA will take place from May 20 until May 25, 2014. (Photo by Patrick Pleul/AP Photo/DPA)

Pumpkins and a mock up skull are seen ahead of Halloween at Wilmersdorfer Strasse shopping street, as the coronavirus disease (COVID-19) outbreak continues, in Berlin, Germany, October 26, 2020. (Photo by Fabrizio Bensch/Reuters)

Yu Jietao, 26-year-old wood carver, sits in his homemade wooden car along a street in Guangfeng county of Shangrao, Jiangxi province, China February 9, 2015. The car can travel as fast as 30 km (18.6 miles) per hour, local media reported. (Photo by Reuters/Stringer)

Protesters take part in “Artists Take Fight Against Police Murders” in New York's Times Square August 13, 2015. (Photo by Brendan McDermid/Reuters)

The face of a graduating student is displayed on a tablet attached to a robot during a “cyber graduation” ceremony at a school on May 22, 2020 in Taguig, Metro Manila, Philippines. Robots represented some 179 graduating students of the Senator Rene Cayetano Science and Technology High School during a graduation ceremony that was streamed online, as mass gatherings remain prohibited in the country under the Philippine government's lockdown to curb the spread of the coronavirus. The robots were developed by alumni of the school's robotics club, which used tablets to display the faces of the graduating students as they “marched” on stage to receive their diplomas. The Philippines' Department of Health has so far reported 13,434 cases of the coronavirus in the country, with at least 846 recorded fatalities. (Photo by Ezra Acayan/Getty Images)

South Vietnamese-born designer Quasar drives the six-foot long square-shaped plastic car he built and which is scheduled to be a hit with the young driving set, in Paris, June 23, 1967. The car can be driven at speeds of up to 60 mph (Photo by Michel Laurent/AP Photo)