This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
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Question: Before World War II, Oklahoma City developed major stockyards, attracting jobs and revenue formerly in Chicago and Omaha, Nebraska. With the 1928 discovery of oil within the city limits (including under the State Capitol), Oklahoma City became a major center of oil production. Post-war growth accompanied the construction of the Interstate Highway System, which made Oklahoma City a major interchange as the convergence of I-35, I-40 and I-44. It was also aided by federal development of Tinker Air Force Base.

Answer: When was oil discovered in the city limits?


Question: During the years 1940-1955, the rate of decline in the U.S. death rate accelerated from 2% per year to 8% per year, then returned to the historical rate of 2% per year. The dramatic decline in the immediate post-war years has been attributed to the rapid development of new treatments and vaccines for infectious disease that occurred during these years. Vaccine development continued to accelerate, with the most notable achievement of the period being Jonas Salk's 1954 development of the polio vaccine under the funding of the non-profit National Foundation for Infantile Paralysis. The vaccine process was never patented, but was instead given to pharmaceutical companies to manufacture as a low-cost generic. In 1960 Maurice Hilleman of Merck Sharp & Dohme identified the SV40 virus, which was later shown to cause tumors in many mammalian species. It was later determined that SV40 was present as a contaminant in polio vaccine lots that had been administered to 90% of the children in the United States. The contamination appears to have originated both in the original cell stock and in monkey tissue used for production. In 2004 the United States Cancer Institute announced that it had concluded that SV40 is not associated with cancer in people.

Answer: When was the Polio vaccine created?


Question: The main cast was revealed in December 2014 at the 007 Stage at Pinewood Studios. Daniel Craig returned for his fourth appearance as James Bond, while Ralph Fiennes, Naomie Harris and Ben Whishaw reprised their roles as M, Eve Moneypenny and Q respectively, having been established in Skyfall. Rory Kinnear also reprised his role as Bill Tanner in his third appearance in the series.

Answer:
When were the actors in Spectre announced?