In this task, you're given a passage, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.

Passage: Kapp received his Abitur from Gymnasium “Hammonense”, the same educational institution where his father held the position of principal. Between 1842 and 1844, Kapp studied law and philosophy at the University of Heidelberg. There, at his uncle Christian Kapp's (1798–1874) house, he met the philosopher Ludwig Feuerbach. Not only did they become close friends; Feuerbach's criticism of religion, which also strongly influenced Karl Marx, had a great impact on Kapp's attitude towards life as well. Other acquaintances from his time as a student were Ludwig Bamberger (1823–1899), who would later become a banker, the author Berthold Auerbach (1812–1882) of Heidelberg and the poet Bettina von Arnim (1785–1859) of Berlin. From 1844 on, Kapp studied at the University of Berlin and voluntarily served in the army for one year. In Berlin, he was already working as a journalist for the utopian socialist magazine called "Westfälisches Dampfboot" ("Westfalian Steamboat").
 Link Information: the author Berthold Auerbach Question: What was one of the books written by the author Kapp knew from his time as a student?
Answer: Biography of Frederick the Great (1834–36)

Passage: In March in Gatineau, Shapovalov captured his fourth ITF Futures singles title after defeating Gleb Sakharov in straight sets. Two weeks later, he won his first ATP Challenger title with a victory over Ruben Bemelmans at the 75K in Drummondville, and was the youngest Canadian to win a Challenger until Félix Auger-Aliassime's victory at the Open Sopra Steria de Lyon later in the year. The next week, he was defeated by Mirza Bašić in the final of the ATP Challenger 50K in Guadalajara, stopping his winning streak at 17 matches. At the French Open in May, his first professional Grand Slam, he was defeated in the first round of qualifying by the first seed Marius Copil in three sets. In June, Shapovalov qualified for the ATP 500 at the Queen's Club Championships, his fourth ATP main draw but his first as a qualifier. In the first round, he defeated his second top 50 player, world No. 47 Kyle Edmund, before losing to world No. 14 Tomáš Berdych. At Wimbledon in July, Shapovalov was awarded a wild card for the main draw. He was defeated by Jerzy Janowicz in the opening round. At the end of the month, he won his second ATP Challenger title, defeating compatriot Peter Polansky in the final of the 75K in Gatineau.
 Link Information: It took place at the Queen's Club in London, United Kingdom Question: In what city does the tournament take place where Shapovalov qualified for the ATP 500 in June?
Answer: London

Passage: The First Indochina War had raged, as guerrilla warfare, since 19 December 1946. From 1949, it evolved into conventional warfare, due largely to aid from the communists of the People's Republic of China ("PRC") to the north. Subsequently, the French strategy of occupying small, poorly defended outposts throughout Indochina, particularly along the Vietnamese-Chinese border, started failing. Thanks to the terrain, popular support for August Revolution and support for decolonization from bordering China and the U.S.S.R., the Viet Minh had succeeded in turning a "clandestine guerrilla movement into a powerful conventional army", following asymmetric warfare theory laid by Mao Tse Tung, something which previously had never been encountered by the western colonial powers. In October 1952, fighting around the Red River Delta spread into the Thai Highlands, resulting in the Battle of Nà Sản, at which the Viet Minh were defeated. The French used the lessons learned at Nà Sản – strong ground bases, versatile air support, and a model based on the British Burma Campaign – as the basis for their new strategy. The Viet Minh, however, remained unbeatable in the highland regions of Vietnam, and the French "could not offset the fundamental disadvantages of a roadbound army facing a hill and forest army in a country which had few roads but a great many hills and forests".
 Link Information: 

The Burma campaign was a series of battles fought in the British colony of Burma, South-East Asian theatre of World War II Question: How many years were there between the end of the British Burma Campaign and the start of the Battle of Na San?

Answer: 7