Elizabeth Mills jumps in front of the Conservative Political Action Conference (CPAC) sign at National Harbor, Md., February 23, 2018. (Photo by Joshua Roberts/Reuters)

A Hong Kong Correctional Services Dog Unit (CSDU) officer demonstrates training at the CSDU training facility in Stanley, Hong Kong, China, 27 February 2018. The Hong Kong CSDU consists of 29 staff members divided across six dog teams. According to the department's latest figure from 2017, the average daily penal population of Hong Kong was 8,529. (Photo by Jérôme Favre/EPA/EFE)

Trainer Lawney Hill poses for a photograph as she wears tights over her face to keep out the cold after taking her horses out on the all-weather gallops in Tetsworth, Britain, March 2, 2018. (Photo by Eddie Keogh/Reuters)

British housewives toss pancakes in skillets as they run through the streets of Olney, England, in the community's annual race which follows a 500-year-old tradition, February 6, 1951. Mrs. Isabel Dix, 22, extreme right, won the race covering the 415 yards from the Parish pump to the door of Sts. Peter and Paul church in one minute, 12.1 seconds. (Photo by AP Photo)

Kelsey Smith of New Zealand gets her stick caught on the shorts of Hollie Pearne-Webb of England during Women's Semi Final Hockey match between England and New Zealand on day eight of the Gold Coast 2018 Commonwealth Games at Gold Coast Hockey Centre on April 12, 2018 on the Gold Coast, Australia. (Photo by Matt King/Getty Images)

Indian men sleep in the shadow of an overflowing cloth container of hay, to be used as animal fodder, on a truck on a hot summer day in Ajmer in the western state of Rajasthan on May 30, 2018. (Photo by Shaukat Ahmed/AFP Photo)

A woman cools off from the extreme heat from an opened fire hydrant in Brooklyn, New York on July 2, 2018. The highest temperature reached 35 degrees Celsius in New York City on Monday as a result of a prolonged heat wave. (Photo by Shannon Stapleton/Reuters)

People gather on a hill near the Chopin Airport to watch aeroplanes taking off, in Warsaw, Poland, Sunday, September 9, 2018. (Photo by Alik Keplicz/AP Photo)