Dancers from the “Legend Lin Dance Theatre” perform the artistic director and choreographer Li-chen Lin's classic works “Hymne aux Fleurs qui Passent, Anthem to the Fading Flowers” during a rehearsal at the National Theater Concert Hall in Taipei, Taiwan, Tuesday, August 18, 2015. “Hymne aux Fleurs Qui Passent” pays tribute to the cycle of the year and the complementary principles of Yin and Yang whose eternal struggle provides the driving force behind the changing of the seasons. (Photo by Chiang Ying-ying/AP Photo)

Iranian Arabs who are members of the paramilitary Basij force march in a military parade marking the 35th anniversary of Iraq's 1980 invasion of Iran, in front of the shrine of late revolutionary founder Ayatollah Khomeini, just outside Tehran, Iran, Tuesday, September 22, 2015. (Photo by Vahid Salemi/AP Photo)

Private Harold L. Langhofer edges into the ball-turret, March 9, 1943. Curled in this position, he can turn the turret so that it fires in any direction. The turret can also be swung around so that the hatch opens into the plane, and the gunner can crawl into it while the Flying Fortress is in motion. (Photo by AP Photo)

Number 10. BELL H-13 SIOUX was a two-bladed, single engine, light helicopter built by Bell Helicopter. Westland Aircraft manufactured the Sioux under license for the British military as the Sioux AH.1 and HT. In 1947, the United States Air Force ordered the improved Bell Model 47A. Most were designated YR-13 and three winterized versions were designated YR-13A. The United States Army first ordered Bell 47s in 1948 under the designation H-13. These would later receive the name Sioux. The Bell-built H-13 B is seen airborne in this April 29, 1951 photo. The helicopter is equipped with a 173 horsepower engine, cruises at 85 miles per hour, climbs 900 feet in a minute and has a service ceiling of 11,500 feet. (Photo by AP Photo)

Tour guides wearing traditional Chinese dress practice smiling by biting chopsticks at Qingming Grand-River Park in Kaifeng, central China's Henan Province on March 2, 2017, aiming to provide better service for visitors. (Photo by IPA Asia via ZUMA Wire)

Christian Bale poses for a fan at the 25th annual Screen Actors Guild Awards at the Shrine Auditorium & Expo Hall on Sunday, January 27, 2019, in Los Angeles. (Photo by Mario Anzuoni/Reuters)

An Armatix employee holds a “smart gun” by the company at the Armatix headquarters in Munich May 14, 2014. The gun is implanted with an electronic chip that allows it to be fired only if the shooter is wearing a watch that communicates with it through a radio signal. If the gun is moved more than 10 inches (25 cm) from the watch, it will not fire. A Maryland gun shop owner has dropped his plan to be the first in the United States to sell the so-called “smart gun” after a backlash that included death threats. (Photo by Michael Dalder/Reuters)

Mother and daughter volunteers Niki, right, and Rachel practice their pancake tossing technique in the streets of Wimborne model town and gardens before taking part in the Wimborne Minster virtual pancake race, in Wimborne, England, Tuesday February 16, 2021. Although a physical race cannot take place this year due to the coronavirus restrictions, Wimborne Minster has invited people to film themselves tossing a pancake for 30 seconds and posting it to Facebook. (Photo by Andrew Matthews/PA Wire via AP Photo)