A medical staff member rests next to a patient infected with Covid-19 in the intensive care unit of Lozenets Hospitalin Sofia on November 9, 2021. Bulgaria is among the countries with the highest number of deaths compared to its population. (Photo by Nikolay Doychinov/AFP Photo)

Steam comes out of the chimneys of the coal-fired power station Neurath near the Garzweiler open-cast coal mine in Luetzerath, Germany, Monday, October 25, 2021. The climate change conference COP26 will start next Sunday in Glasgow, Scotland. (Photo by Michael Probst/AP Photo)

The owner of the zoo Pierre Thivillon laughs next to a chimpanzee on May 17, 2021, at the zoological park of Saint-Martin-la-Plaine, two days ahead of its reopening as part of France's latest step toward the ending of its third nationwide Covid-19 lockdown. (Photo by Jean-Philippe Ksiazek/AFP Photo)

Tia the springer spaniel chases after the ball as owner Monika Burton falls over in the background. The funny scene was captured by husband, Vince Burton at Wells Next The Sea, Norfolk, on Easter Monday, April 18, 2022. (Photo by Vince Burton/Animal News Agency)

Dancers from Cuba's National Ballet rehearse under the leadership of U.S. choreographer Jessica Lang as they prepare next month's International Ballet Festival in Havana, Cuba, Thursday, September 1, 2022. (Photo by Ramon Espinosa/AP Photo)

Carlos Boozer #5 of the Chicago Bulls grabs a rebound next to David West #30 of the New Orleans Hornets at the United Center on March 7, 2011 in Chicago, Illinois. The Bulls defeated the Hornets 85-77.

Adam Ghiggio from Australia poses next to mutant mannequins which are lined up to be used as displays for the new video game “Rage” at the Los Angeles Convention Center on June 5, 2011 in Los Angeles, California. The Electronic Entertainment Expo officially starts on Tuesday. (Photo by Kevork Djansezian/Getty Images)

Google has built its first self-driving car prototypes and hopes to test hundreds more models this summer. If all goes well, the company is planning a pilot program in California over the next few years.