Senator Barack Obama (D-IL) (R) stands in front of Senator Hillary Clinton (D-NY) as they arrive for U.S. President George W. Bush's annual State of the Union speech to a joint session of Congress at the U.S. Capitol in Washington in this January 23, 2007 file photo. Hillary Clinton announced her second run for the presidency on April 12, 2015 starting her campaign as the Democrats' best hope of fending off a crowded field of lesser-known Republican rivals and retaining the White House. (Photo by Larry Downing/Reuters)

Boys play with a drainage culvert used for flood control in Las Pinas, Metro Manila February 28, 2016. (Photo by Erik De Castro/Reuters)

Revellers ride during the 54th annual brass band festival in the Serbian village of Guca August 7, 2014. Every year Guca is swamped by thousands of people taking part in the celebration of brass band music. (Photo by Marko Djurica/Reuters)

A person viewing the Northern lights over the lava landscape, Reykjanes Peninsula, Iceland. (Photo by Arctic-Images/Getty Images)

A girl uses her mobile phone during the evening at the National Park in Khartoum, Sudan, April 24, 2015. (Photo by Mohamed Nureldin Abdallah/Reuters)

U.S. Army helicopters providing support for U.S. ground troops fly into a staging area fifty miles northeast of Saigon, Vietnam, August 28, 1966. Helicopter fuel is stored in the large rubber tanks, foreground. (Photo by Henri Huet/AP Photo)

All the drugery of dishwashing in this three-times -a day task, which comes to the house wife who does her own house work, has been eliminated by the new dish washer shown in the photograph on April 25, 1921. It is the invention of a Cincinnati school teacher, who sought to make things a bit more pleasant for his wife. Incedently, his idea was worth 12,00 to him, for a manufacturing concern thought so much of the “dish-washer” they purchased the rights and will seek to add a little joy to thousands of other housewives. With the aid of only hot water, dishes placed in a wire rack and set into the drum are made clean and spotless in two minutes. (Photo by Bettmann Archive/Getty Images)

A young child reaches out to a Gentoo penguin as it swims in its enclosure at Pairi Daiza Park in Cambron-Casteau, Belgium, Monday, July 5, 2021. Pairi Daiza, one of the biggest zoos in Europe, has recently added ten Gentoo penguins to their animal population. (Photo by Virginia Mayo/AP Photo)