Problem: Greece:

The principal gods of the ancient Greek religion were the Dodekatheon, or the Twelve Gods, who lived on the top of Mount Olympus. The most important of all ancient Greek gods was Zeus, the king of the gods, who was married to Hera, who was also Zeus's sister. The other Greek gods that made up the Twelve Olympians were Demeter, Ares, Poseidon, Athena, Dionysus, Apollo, Artemis, Aphrodite, Hephaestus and Hermes. Apart from these twelve gods, Greeks also had a variety of other mystical beliefs, such as nymphs and other magical creatures.

Who was Zeus's sister?
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A: Hera


Problem: San Diego is served by the San Diego Trolley light rail system, by the SDMTS bus system, and by Coaster and Amtrak Pacific Surfliner commuter rail; northern San Diego county is also served by the Sprinter light rail line. The Trolley primarily serves downtown and surrounding urban communities, Mission Valley, east county, and coastal south bay. A planned Mid-Coast extension of the Trolley will operate from Old Town to University City and the University of California, San Diego along the I-5 Freeway, with planned operation by 2018. The Amtrak and Coaster trains currently run along the coastline and connect San Diego with Los Angeles, Orange County, Riverside, San Bernardino, and Ventura via Metrolink and the Pacific Surfliner. There are two Amtrak stations in San Diego, in Old Town and the Santa Fe Depot downtown. San Diego transit information about public transportation and commuting is available on the Web and by dialing "511" from any phone in the area.
How many Amtrak stations are in San Francisco?
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Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
New Delhi is home to several historic sites and museums. The National Museum which began with an exhibition of Indian art and artefacts at the Royal Academy in London in the winter of 1947–48 was later at the end was shown at the Rashtrapati Bhawan in 1949. Later it was to form a permanent National Museum. On 15 August 1949, the National Museum was formally inaugurated and currently has 200,000 works of art, both of Indian and foreign origin, covering over 5,000 years.
On what date was the National Museum formally inaugurated?
A: 15 August 1949


Context and question: Blues rock acts that pioneered the sound included Cream, The Jimi Hendrix Experience, and The Jeff Beck Group. Cream, in songs like "I Feel Free" (1966) combined blues rock with pop and psychedelia, particularly in the riffs and guitar solos of Eric Clapton. Jimi Hendrix produced a form of blues-influenced psychedelic rock, which combined elements of jazz, blues and rock and roll. From 1967 Jeff Beck brought lead guitar to new heights of technical virtuosity and moved blues rock in the direction of heavy rock with his band, The Jeff Beck Group. Dave Davies of The Kinks, Keith Richards of The Rolling Stones, Pete Townshend of The Who, Hendrix, Clapton and Beck all pioneered the use of new guitar effects like phasing, feedback and distortion. The Beatles began producing songs in the new hard rock style beginning with the White Album in 1968 and, with the track "Helter Skelter", attempted to create a greater level of noise than the Who. Stephen Thomas Erlewine of AllMusic has described the "proto-metal roar" of "Helter Skelter," while Ian MacDonald argued that "their attempts at emulating the heavy style were without exception embarrassing."
Who was the guitarist for the band Cream?
Answer: Eric Clapton


Question: During the 19th century, Karl Marx and Friedrich Engels extended the concept of materialism to elaborate a materialist conception of history centered on the roughly empirical world of human activity (practice, including labor) and the institutions created, reproduced, or destroyed by that activity (see materialist conception of history). Later Marxists developed the notion of dialectical materialism which characterized later Marxist philosophy and method.
Is there an answer to this question: Who was Karl Marx's enemy? 

Answer: unanswerable


In February 2016, over a hundred thousand people signed a petition in just twenty-four hours, calling for a boycott of Sony Music and all other Sony-affiliated businesses after rape allegations against music producer Dr. Luke were made by musical artist Kesha. Kesha asked a New York City Supreme Court to free her from her contract with Sony Music but the court denied the request, prompting widespread public and media response. 
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): How many people signed a petition to boycott Sony Music in 2016?
Ah, so..
over a hundred thousand