Problem: Airport:

The majority of the world's airports are non-towered, with no air traffic control presence. Busy airports have air traffic control (ATC) system. All airports use a traffic pattern to assure smooth traffic flow between departing and arriving aircraft. There are a number of aids available to pilots, though not all airports are equipped with them. Many airports have lighting that help guide planes using the runways and taxiways at night or in rain, snow, or fog. In the U.S. and Canada, the vast majority of airports, large and small, will either have some form of automated airport weather station, a human observer or a combination of the two. Air safety is an important concern in the operation of an airport, and airports often have their own safety services.

What is an important concern for pilots?
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A: unanswerable

Problem: Apollo:

Apollo (Attic, Ionic, and Homeric Greek: , Apollon (GEN ); Doric: , Apellon; Arcadocypriot: , Apeilon; Aeolic: , Aploun; Latin: Apollo) is one of the most important and complex of the Olympian deities in classical Greek and Roman religion and Greek and Roman mythology. The ideal of the kouros (a beardless, athletic youth), Apollo has been variously recognized as a god of music, truth and prophecy, healing, the sun and light, plague, poetry, and more. Apollo is the son of Zeus and Leto, and has a twin sister, the chaste huntress Artemis. Apollo is known in Greek-influenced Etruscan mythology as Apulu.

What name is Apollo known by in Etruscan mythology?
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A: Apulu

Problem: Frederic Chopin:

Chopin's tombstone, featuring the muse of music, Euterpe, weeping over a broken lyre, was designed and sculpted by Clesinger. The expenses of the funeral and monument, amounting to 5,000 francs, were covered by Jane Stirling, who also paid for the return of the composer's sister Ludwika to Warsaw. Ludwika took Chopin's heart in an urn, preserved in alcohol, back to Poland in 1850.[n 9] She also took a collection of two hundred letters from Sand to Chopin; after 1851 these were returned to Sand, who seems to have destroyed them.

Who ended up with the 200 letters from Sand to Chopin?
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A: Sand

Problem: Rajasthan:

Rajasthan attracted 14 percent of total foreign visitors during 20092010 which is the fourth highest among Indian states. It is fourth also in Domestic tourist visitors. Tourism is a flourishing industry in Rajasthan. The palaces of Jaipur and Ajmer-Pushkar, the lakes of Udaipur, the desert forts of Jodhpur, Taragarh Fort (Star Fort) in Ajmer, and Bikaner and Jaisalmer rank among the most preferred destinations in India for many tourists both Indian and foreign. Tourism accounts for eight percent of the state's domestic product. Many old and neglected palaces and forts have been converted into heritage hotels. Tourism has increased employment in the hospitality sector.

What percentage of India's foreign visitors came to Rajasthan from 2009 to 2010?
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A:
14 percent