Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Liberia is divided into fifteen counties, which, in turn, are subdivided into a total of 90 districts and further subdivided into clans. The oldest counties are Grand Bassa and Montserrado, both founded in 1839 prior to Liberian independence. Gbarpolu is the newest county, created in 2001. Nimba is the largest of the counties in size at 11,551 km2 (4,460 sq mi), while Montserrado is the smallest at 1,909 km2 (737 sq mi). Montserrado is also the most populous county with 1,144,806 residents as of the 2008 census.
How many clans is Liberia divided into?
A: unanswerable

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The Heian period (平安時代, Heian jidai?) is the last division of classical Japanese history, running from 794 to 1185. The period is named after the capital city of Heian-kyō, or modern Kyōto. It is the period in Japanese history when Buddhism, Taoism and other Chinese influences were at their height. The Heian period is also considered the peak of the Japanese imperial court and noted for its art, especially poetry and literature. Although the Imperial House of Japan had power on the surface, the real power was in the hands of the Fujiwara clan, a powerful aristocratic family who had intermarried with the imperial family. Many emperors actually had mothers from the Fujiwara family. Heian (平安?) means "peace" in Japanese.
The Heian period was known for what types of art?
A: poetry and literature

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The density of paper ranges from 250 kg/m3 (16 lb/cu ft) for tissue paper to 1,500 kg/m3 (94 lb/cu ft) for some speciality paper. Printing paper is about 800 kg/m3 (50 lb/cu ft).
What is the lightest density of wood produced?
A: unanswerable

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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.)
What were potential benefits of the CD-4 format?
A:
reduced distortion and greater headroom