Problem:Passage: The first use of X-rays under clinical conditions was by John Hall-Edwards in Birmingham, England on 11 January 1896, when he radiographed a needle stuck in the hand of an associate. On February 14, 1896 Hall-Edwards was also the first to use X-rays in a surgical operation. In early 1896, several weeks after Rontgen's discovery, Ivan Romanovich Tarkhanov irradiated frogs and insects with X-rays, concluding that the rays "not only photograph, but also affect the living function".

Question: Based on this passage, when were x rays first used in medicine?
Solution:OK... The relevant information is: The first use of X-rays under clinical conditions was by John Hall-Edwards in Birmingham, England on 11 January 1896, when he radiographed a needle stuck in the hand of an associate.
11 January 1896.

Problem:War and Peace (pre-reform Russian: ; post-reform Russian: , translit. Voyna i mir ( vjna i mjir) ) is a novel by the Russian author Leo Tolstoy, which is regarded as a central work of world literature and one of Tolstoy's finest literary achievements.

Based on this passage, who wrote the classic novel war and peace?
Solution:OK... The relevant sentence in the passage is: War and Peace (pre-reform Russian: ; post-reform Russian: , translit. Voyna i mir ( vjna i mjir) ) is a novel by the Russian author Leo Tolstoy, which is regarded as a central work of world literature and one of Tolstoy's finest literary achievements.
Leo Tolstoy.

Problem:William December "Billy Dee" Williams Jr. (born April 6, 1937) is an American actor, artist, singer, and writer. He is best known for his role as Lando Calrissian in the Star Wars film franchise. Williams has also appeared in critically acclaimed films like Brian's Song, Lady Sings the Blues, Mahogany, Nighthawks, and Batman; in which he played Harvey Dent.

Answer this question: who is the actor that played lando calrissian?
Solution:
OK... To answer the above question, the relevant sentence is: He is best known for his role as Lando Calrissian in the Star Wars film franchise.
William December '' Billy Dee '' Williams Jr..