People cross Flagstaff Hill as the snow starts to fall, in Schenley Park, on their way to the Carnegie Mellon University campus, Tuesday, March 20, 2018, in the Oakland section of Pittsburgh. Yet another powerful storm bore down on the Northeast on Tuesday, with wind-whipped snow falling in parts of Pennsylvania and New Jersey as people grumbled and complained about a first day of spring that looked an awful lot like the last weeks of winter. (Photo by Darrell Sapp/Pittsburgh Post-Gazette via AP Photo)

A man wearing a mask looks on as he sells matresses in Manila, Philippines, January 8, 2020. (Photo by Willy Kurniawan/Reuters)

Cheerleaders wearing face masks due to the outbreak of the coronavirus disease (COVID-19) are seen at the first professional baseball league game of the season at Taoyuan International baseball stadium in Taoyuan city, Taiwan, April 11, 2020. (Photo by Ann Wang/Reuters)

The full moon rises behind the cooling towers of the nuclear power station in Philippsburg, Germany, 06 May 2020. The nuclear power plant in Philippsburg was completely shut down by 31 December 2019. According to the operator EnBW, the two cooling towers are expected to be demolished by blasting on 14-15 May 2020. (Photo by Ronald Wittek/EPA/EFE)

A Grevy’s zebra gets itself noticed at ZSL Whipsnade Zoo in Whipsnade, England on April 20, 2018. (Photo by Tony Margiocchi/Barcroft Media)

An alligator named Muja is seen in its enclosure in Belgrade's Zoo, Serbia, August 14, 2018. Muja is officially the oldest American alligator in the world living in captivity. He was brought to Belgrade from Germany in 1937, a year after the opening of the Zoo. Muja survived three bombings of Belgrade, the Second World War and all hardships the Zoo went through. (Photo by Marko Djurica/Reuters)

In this photo taken on Thursday, September 6, 2018, a women releases an arrow during an archery competition during the Third Nomad Games, in Cholpon-Ata, 250 kilometers (156 miles) of Bishkek, Kyrgyzstan. The Central Asian nation of Kyrgyzstan held its biennial Nomad Games to promote and celebrate traditional sports of nomadic people. The week-long competition, which is held in a gorge near the picturesque Lake Issyk-Kul, feature traditional sports of nomad peoples such as horseback wrestling and goat polo. (Photo by Vladimir Voronin/AP Photo)

A security man keeps guard during Malawi's President elect Arthur Peter Mutharika swearing in ceremony at Kamuzu Stadium in Blantyre on May 28, 2019, after a contentious election marred by allegations of fraud and vote-rigging. The Malawi Electoral Commission announced on Monday that Mutharika, who heads the ruling Democratic Progressive Party (DPP), had narrowly won last week's vote after an injunction barring the release of the results was lifted. (Photo by Amos Gumulira/AFP Photo)