In this task, you're given a passage, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both passage and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the passage or linked information.
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Question: Passage: In 1479, the Lord of Bearn, Francis Phoebus, inherited the Kingdom of Navarre, across the Pyrenees to the southwest. The two sovereign principalities remained in personal union until their extinction. Bearn went on to be ruled by Henry II of Navarre, who inherited it from his mother. In 1512, the Kingdom of Navarre was almost entirely occupied by Spain; only Lower Navarre, north of the Pyrenees escaped Spanish permanent occupation. The Bearnese monarchs extended the use of Occitan to Navarre after 1512, despite the fact that it was not the vernacular there, where Basque was the tongue of the people. The Estates of Navarre convoked in 1522 (or in 1523, according to other sources) kept records in Occitan, as did the Chancery of Navarre created in 1524. When Henry II revised the Fueros of Navarre in 1530, he had them translated from Castilian into Occitan.
Link Information: Queen Eleanor succeeded him for only 15 days and died, leaving the crown to her grandson, Francis Phoebus Answer: Queen Eleanor

Answer: Who did Francis Phoebus inherit the Kingdom of Navarre from?

Question: Passage: Walsh first developed what would become the West Coast offense when he was offensive coordinator of the Cincinnati Bengals, working under legendary head coach Paul Brown. However, Walsh truly perfected this strategy as the head coach of the San Francisco 49ers. His teams were led by quarterback Joe Montana. Montana, who was noted for his ability to remain calm under pressure, also possessed good mobility and an accurate passing arm. Another important player in the 49ers offense was Roger Craig, a swift, speedy running back who could also catch passes out of the backfield and was a good receiver. Walsh's 49ers teams also featured several All-Pro wide receivers, including Dwight Clark, John Taylor, and Jerry Rice. The 49ers were one of the NFL's powerhouses in the 1980s and 1990s, under the guidance of head coaches Bill Walsh (19791988) and George Seifert (19891996). Walsh won three Super Bowls in the 1981, 1984 and 1988 seasons. Seifert won two Super Bowls in 1989 and 1994. Montana, Walsh and Rice are in the Pro Football Hall of Fame, and so is Montana's successor, quarterback Steve Young. Like Montana, Young was a great running quarterback and a very efficient passer.
Link Information: In the spring of 1993, at Montana's request, San Francisco traded Montana to the Kansas City Chiefs. Young was now the 49ers' undisputed starter, Answer: 1993

Answer: What year did Montana's successor take over?

Question: Passage: DeGolyer opened a petroleum geology consultancy in 1914, moving to Montclair, New Jersey to work in New York City in 1916. In 1919, while working as a consultant to the British entrepreneur Lord Cowdray, DeGolyer negotiated the sale of the El Aguila company to Royal Dutch Shell. In the same year, DeGolyer organized the formation of the Rycade Oil Company as well as the Amerada Petroleum Corporation for Lord Cowdray, rising to become general manager, president, and chairman from 1929 to 1932 DeGolyer left the firm in 1932, but remained with Rycade, which was established to explore salt dome oil deposits through 1941. As a geophysical consultant with Rycade, DeGolyer made the first torsion balance survey in the United States at the Spindletop oilfield. An oilfield found by DeGolyer on behalf of Rycade at Nash, Texas was the first oilfield anywhere to be discovered using geophysics. From 1925 DeGolyer established the Geophysical Research Corporation as a subsidiary of Amerada to develop reflection seismology techniques originated by J. Clarence Karcher and Eugene McDermott, leaving in 1932 to move to Dallas, Texas. DeGolyer provided financial support for the 1930 establishment of GRC's successor, Geophysical Service Incorporated. GSI went on to spin off Texas Instruments. In 1936 with Lewis MacNaughton, DeGolyer established the petroleum exploration consulting firm DeGolyer and MacNaughton, and Core Laboratories, Incorporated the same year to provide drilling core and fluids analysis. DeGolyer was also associated with the Atlatl Royalty Company from 1932 to 1950 and the Felmont Corporation in 1934. In 1956 he established Isotopes, Incorporated to provide radioactive isotopes for oilfield and industrial purposes.
Link Information: The Royal Dutch Shell Group was created in April 1907 Answer: 12

Answer:
How long had Royal Dutch Shell been a company for the year it purchased El Aguila?