Problem: Economy of Greece:

Greece's rail network is estimated to be at 2,548 km. Rail transport in Greece is operated by TrainOSE, a subsidiary of the Hellenic Railways Organization (OSE). Most of the country's network is standard gauge (1,565 km), while the country also has 983 km of narrow gauge. A total of 764 km of rail are electrified. Greece has rail connections with Bulgaria, the Republic of Macedonia and Turkey. A total of three suburban railway systems (Proastiakos) are in operation (in Athens, Thessaloniki and Patras), while one metro system is operational in Athens with another under construction.

How many kilometers of Greece's railway is gold?
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A: unanswerable

Problem: Circadian rhythm:

The rhythm is linked to the lightdark cycle. Animals, including humans, kept in total darkness for extended periods eventually function with a free-running rhythm. Their sleep cycle is pushed back or forward each "day", depending on whether their "day", their endogenous period, is shorter or longer than 24 hours. The environmental cues that reset the rhythms each day are called zeitgebers (from the German, "time-givers"). Totally blind subterranean mammals (e.g., blind mole rat Spalax sp.) are able to maintain their endogenous clocks in the apparent absence of external stimuli. Although they lack image-forming eyes, their photoreceptors (which detect light) are still functional; they do surface periodically as well.[page needed]

What do blind mole rats have in place of vision?
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A: photoreceptors

Problem: Super Nintendo Entertainment System:

Nintendo of America took the same stance against the distribution of SNES ROM image files and the use of emulators as it did with the NES, insisting that they represented flagrant software piracy. Proponents of SNES emulation cite discontinued production of the SNES constituting abandonware status, the right of the owner of the respective game to make a personal backup via devices such as the Retrode, space shifting for private use, the desire to develop homebrew games for the system, the frailty of SNES ROM cartridges and consoles, and the lack of certain foreign imports.

What device allows backing up SNES games?
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A: Retrode

Problem: House music:

Derrick May a.k.a. "MAYDAY" and Thomas Barnett released "Nude Photo" in 1987 on May's label "Transmat Records", which helped kickstart the Detroit techno music scene and was put in heavy rotation on Chicago's Hot Mix 5 Radio DJ mix show and in many Chicago clubs.[citation needed] A year later, Transmat released what was to become one of techno and house music's classic anthems the seminal track "Strings of Life". Transmat Records went on to have many more successful releases[citation needed] such as 1988's "Wiggin". As well, Derrick May had successful[citation needed] releases on Kool Kat Records and many remixes for a host of underground and mainstream recording artist.

What was the real name of the artist Mayday?
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A:
Derrick May