Law enforcement officers stand, with some turning their backs, as New York City Mayor Bill de Blasio speaks on a monitor outside the funeral for NYPD officer Wenjian Liu in the Brooklyn borough of New York January 4, 2015. Tens of thousands of law enforcement officers from across the country gathered on Sunday for the funeral of the second of two New York City policemen killed last month in an ambush that galvanized critics of Mayor de Blasio. (Photo by Shannon Stapleton/Reuters)

School teachers and staff members take part during an active shooter training at James I. O'Neill High School in Highland Falls, New York, U.S., December 12, 2017. (Photo by Eduardo Munoz/Reuters)

Chinese women holding toy guns dance for a revolutionary song during their daily exercise at a square outside a shopping mall in Beijing, June 29, 2014. About 30 local residents formed this “Nanguan” art group that enjoys performing to revolutionary songs and dance performances as part of their daily fitness activities at night. (Photo by Jason Lee/Reuters)

People wait at a bus stop during heavy rain in Kathmandu, Nepal on September 21, 2020. The government eased the coronavirus lockdown for economic activities despite the number of COVID-19 cases is on the rise in Nepal. (Photo by Narendra Shrestha/EPA/EFE/Rex Features/Shutterstock)

Smoke and ash are visible during the the Shiveluch volcano's eruption on the Kamchatka Peninsula in Russia, Tuesday, April 11, 2023. Shiveluch, one of Russia's most active volcanoes, erupted Tuesday, spewing clouds of ash 20 kilometers into the sky and covering broad areas with ash. (Photo by Alexander Ledyayev via AP Photo)

Children listen to speakers as U.S. President Joe Biden and first lady Jill Biden host a barbeque with active-duty military families on the South Lawn at the White House in Washington, U.S., July 4, 2023. (Photo by Julia Nikhinson/Reuters)

Take a look at this stunning photo of Tolbachik, an active volcanic complex on the Kamchatka Peninsula in far eastern Russia. Lava fountains and rivers ran through the area for months after the eruption began with the opening of two Tolbachik fissures in November of 2012. In the midst of this activity, photographers Luda and Andrey (lusika33) took a trip down to see that stunning hell valley on earth. (Photo by lusika33)

Air conditioners, more than 500 in total, hang on the wall of an office building on August 15, 2011 in Fuzhou, Fujiang Province of China. This 25-story office building was built with no central air conditioner system, each office has it own individual unit installed on the exterior creating this wall of air conditioners. (Photo by ChinaFotoPress/Getty Images)