In this May 24, 2018 file photo, rain drops accumulate on a car's windshield as commuters wait at a red light in Havana, Cuba. (Photo by Desmond Boylan/AP Photo)

Blankets cover the bodies of a woman (right) and a man (left background) hit by a northbound Penn Central train (background) as they waited with a crowd at Pennsylvania Railroad station in Elizabeth, N.J. on June 8, 1968 to view the southbound train carrying the body of Sen. Robert F. Kennedy to Washington. The woman was identified as Mrs. Antoinette Severini, 54, and the man, John Curia (age unavailable), both of Elizabeth. (Photo by AP Photo)

Two and a half year-old Jennifer Martin in tears during a visit to Santa at Harrods department store in London, 10th December 1949. (Photo by William Vanderson/Fox Photos/Hulton Archive/Getty Images)

An Army Sikorsky R-5 helicopter, undergoing record trials, demonstrates its lifting power by carrying 17 persons and pilot aloft as female onlookers wave in Bridgeport, Conn., January 10, 1946. During the tests records were claimed for altitude speed and both altitude and speed with payload. (Photo by Anthony Camerano/AP Photo)

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)

A Tibetan artists wearing a traditional costume waits before their performance during the 82nd pre-birthday celebration of Tibetan spiritual leader Dalai Lama at a Monastery in Kathmandu, Nepal, 05 July 2017. More than 1,000 monks and other Tibetans gathered at the Monastery compound to celebrate their spiritual leader's birthday. The Nepalese government has banned all kinds of Tibetan activities against the Chinese rule in Tibet so Tibetans have been changing the venue of the Dalai Lama's birthday celebration. The Dalai Lama will turn 82 on 06 July 2017. (Photo by Narendra Shrestha/EPA)

“Be prepared” is the motto of petite Doris Sherrell, vocalist and dancer with “Blackouts of 1942”. In the event of a bombing, the young lady had her social security number tattooed on one leg by artist Jack Julian, and address placed on the other limb for means of identification in Los Angeles, September 29, 1942. (Photo by AP Photo)

Belarusian schoolchildren, who are members of a pro-government Young Pioneer movement, perform with drums as they take part in a meeting to mark the 95th anniversary of their organisation in Minsk, Belarus May 19, 2017. (Photo by Vasily Fedosenko/Reuters)