Problem: Miami:

Miami's heavy-rail rapid transit system, Metrorail, is an elevated system comprising two lines and 23 stations on a 24.4-mile (39.3 km)-long line. Metrorail connects the urban western suburbs of Hialeah, Medley, and inner-city Miami with suburban The Roads, Coconut Grove, Coral Gables, South Miami and urban Kendall via the central business districts of Miami International Airport, the Civic Center, and Downtown. A free, elevated people mover, Metromover, operates 21 stations on three different lines in greater Downtown Miami, with a station at roughly every two blocks of Downtown and Brickell. Several expansion projects are being funded by a transit development sales tax surcharge throughout Miami-Dade County.

How many lines doesn't Metromover have?
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A: unanswerable

Problem: Although the two displayed great respect and admiration for each other, their friendship was uneasy and had some qualities of a love-hate relationship. Harold C. Schonberg believes that Chopin displayed a "tinge of jealousy and spite" towards Liszt's virtuosity on the piano, and others have also argued that he had become enchanted with Liszt's theatricality, showmanship and success. Liszt was the dedicatee of Chopin's Op. 10 Etudes, and his performance of them prompted the composer to write to Hiller, "I should like to rob him of the way he plays my studies." However, Chopin expressed annoyance in 1843 when Liszt performed one of his nocturnes with the addition of numerous intricate embellishments, at which Chopin remarked that he should play the music as written or not play it at all, forcing an apology. Most biographers of Chopin state that after this the two had little to do with each other, although in his letters dated as late as 1848 he still referred to him as "my friend Liszt". Some commentators point to events in the two men's romantic lives which led to a rift between them; there are claims that Liszt had displayed jealousy of his mistress Marie d'Agoult's obsession with Chopin, while others believe that Chopin had become concerned about Liszt's growing relationship with George Sand.
What did Frederic receive from Liszt when the latter performed a nocturne with certain embellishments added?
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Answer: an apology

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
A different format, CD-4 (not to be confused with compact disc), by RCA, encoded the front-rear difference information on an ultrasonic carrier, which required a special wideband cartridge to capture it on carefully calibrated pickup arm/turntable combinations. CD-4 was even less successful than the two matrixed formats. (A further problem was that no cutting heads were available that could handle the HF information. That was remedied by cutting at half the speed. Later, the special half-speed cutting heads and equalization techniques were employed to get a wider frequency response in stereo with reduced distortion and greater headroom.)
How widespread was the success of CD-4 format?
A: even less successful than the two matrixed formats

Context and question: Mathematics: The earliest traces of mathematical knowledge in the Indian subcontinent appear with the Indus Valley Civilization (c. 4th millennium BC ~ c. 3rd millennium BC). The people of this civilization made bricks whose dimensions were in the proportion 4:2:1, considered favorable for the stability of a brick structure. They also tried to standardize measurement of length to a high degree of accuracy. They designed a rulerthe Mohenjo-daro rulerwhose unit of length (approximately 1.32 inches or 3.4 centimetres) was divided into ten equal parts. Bricks manufactured in ancient Mohenjo-daro often had dimensions that were integral multiples of this unit of length.
What proportional size were the bricks that the civilization used?
Answer: 4:2:1

Question: In his 2004 presidential campaign, Kerry criticized George W. Bush for the Iraq War. He and his running mate, North Carolina Senator John Edwards, lost the election, finishing 35 electoral votes behind Bush and Vice President Dick Cheney. Kerry returned to the Senate, becoming Chairman of the Senate Committee on Small Business and Entrepreneurship in 2007 and then of the Foreign Relations Committee in 2009. In January 2013, Kerry was nominated by President Barack Obama to succeed outgoing Secretary of State Hillary Clinton and then confirmed by the U.S. Senate, assuming the office on February 1, 2013.
Is there an answer to this question: When did Kerry run for president?

Answer: 2004

The terms "language" and "dialect" are not necessarily mutually exclusive: There is nothing contradictory in the statement "the language of the Pennsylvania Dutch is a dialect of German".
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Which terms are always mutually exclusive?
Ah, so..
unanswerable