Problem: Lighting:

Flares can also be used by the military to mark positions, usually for targeting, but laser-guided and GPS weapons have eliminated this need for the most part.

What has eliminated the need for flares on a battlefield?
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A: laser-guided and GPS weapons

Problem: Tucson's primary electrical power source is a coal and natural gas power-plant managed by Tucson Electric Power that is situated within the city limits on the south-western boundary of Davis-Monthan Air-force base adjacent to Interstate-10. The air pollution generated has raised some concerns as the Sundt operating station has been online since 1962 as is exempt from many pollution standards and controls due to its age. Solar has been gaining ground in Tucson with its ideal over 300 days of sunshine climate. Federal, state, and even local utility credits and incentives have also enticed residents to equip homes with solar systems. Davis-Monthan AFB has a 3.3 Megawatt (MW) ground-mounted solar photovoltaic (PV) array and a 2.7 MW rooftop-mounted PV array, both of which are located in the Base Housing area. The base will soon have the largest solar-generating capacity in the United States Department of Defense after awarding a contract on September 10, 2010, to SunEdison to construct a 14.5 MW PV field on the northwestern side of the base.
How many days of sunshine does Tucson get each year?
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Answer: over 300

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Goetz set out an ambitious schedule. Universal-International became responsible for the American distribution of Rank's British productions, including such classics as David Lean's Great Expectations (1946) and Laurence Olivier's Hamlet (1948). Broadening its scope further, Universal-International branched out into the lucrative non-theatrical field, buying a majority stake in home-movie dealer Castle Films in 1947, and taking the company over entirely in 1951. For three decades, Castle would offer "highlights" reels from the Universal film library to home-movie enthusiasts and collectors. Goetz licensed Universal's preUniversal-International film library to Jack Broeder's Realart Pictures for cinema re-release but Realart was not allowed to show the films on television.
Who took over Castle Films in 1947?
A: unanswerable

Context and question: The economy began to recover in the early 1960s, and the city experienced explosive population growth through immigration spurred by the jobs created with the implementation of major urban projects and infrastructure improvements. With the advent of democracy in Spain, the ancient kingdom of Valencia was established as a new autonomous entity, the Valencian Community, the Statute of Autonomy of 1982 designating Valencia as its capital. On the night of 23 February 1981, shortly after Antonio Tejero had stormed Congress, the Captain General of the Third Military Region, Jaime Milans del Bosch, rose up in Valencia, put tanks on the streets, declared a state of emergency and tried to convince other senior military figures to support the coup. After the televised message of King Juan Carlos I, those in the military who had not yet aligned themselves decided to remain loyal to the government, and the coup failed. Despite this lack of support, Milans del Bosch only surrendered at 5 a.m. on the next day, 24 February.
When democracy began in Spain, what did the kingdom of Valencia become?
Answer: the Valencian Community

Question: The median income for a household in the city was $26,969, and the median income for a family was $31,997. Males had a median income of $25,471 versus $23,863 for females. The per capita income for the city was $15,402. About 19.1% of families and 23.6% of the population were below the poverty line, including 29.1% of those under age 18 and 18.9% of those age 65 or over.
Is there an answer to this question: What was the median income for a family in the city?

Answer: $31,997

Problem: 2008 Sichuan earthquake:

By May 15, Premier Wen Jiabao ordered the deployment of an additional 90 helicopters, of which 60 were to be provided by the PLAAF, and 30 were to be provided by the civil aviation industry, bringing the total of number of aircraft deployed in relief operations by the air force, army, and civil aviation to over 150, resulting in the largest non-combat airlifting operation in People's Liberation Army history.

How many helicopter were to be provided by the civil aviation industry?
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A:
30