Problem: Circadian rhythm:

The earliest recorded account of a circadian process dates from the 4th century B.C.E., when Androsthenes, a ship captain serving under Alexander the Great, described diurnal leaf movements of the tamarind tree. The observation of a circadian or diurnal process in humans is mentioned in Chinese medical texts dated to around the 13th century, including the Noon and Midnight Manual and the Mnemonic Rhyme to Aid in the Selection of Acu-points According to the Diurnal Cycle, the Day of the Month and the Season of the Year.

What is the earliest recorded instance of circadian rhythm?
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A: 4th century B.C.E

Problem: Symbiosis (from Greek "together" and "living") is close and often long-term interaction between two different biological species. In 1877 Albert Bernhard Frank used the word symbiosis (which previously had been used to depict people living together in community) to describe the mutualistic relationship in lichens. In 1879, the German mycologist Heinrich Anton de Bary defined it as "the living together of unlike organisms."
What nationality was Albert Bernhard Frank?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The U.S. Army currently consists of 10 active divisions as well as several independent units. The force is in the process of contracting after several years of growth. In June 2013, the Army announced plans to downsize to 32 active combat brigade teams by 2015 to match a reduction in active duty strength to 490,000 soldiers. Army Chief of Staff Raymond Odierno has projected that by 2018 the Army will eventually shrink to "450,000 in the active component, 335,000 in the National Guard and 195,000 in U.S. Army Reserve."
How many brigade teams did the Navy downsize to by 2015?
A: unanswerable

Context and question: In mid-2004 Madonna embarked on the Re-Invention World Tour in the U.S., Canada, and Europe. It became the highest-grossing tour of 2004, earning around $120 million and became the subject of her documentary I'm Going to Tell You a Secret. In November 2004, she was inducted into the UK Music Hall of Fame as one of its five founding members, along with The Beatles, Elvis Presley, Bob Marley, and U2. In January 2005, Madonna performed a cover version of the John Lennon song "Imagine" at Tsunami Aid. She also performed at the Live 8 benefit concert in London in July 2005.
When was the Re-Invention World Tour kick off?
Answer: mid-2004

Question: For any prime number p, there is also the multiplicative group of integers modulo p. Its elements are the integers 1 to p 1. The group operation is multiplication modulo p. That is, the usual product is divided by p and the remainder of this division is the result of modular multiplication. For example, if p = 5, there are four group elements 1, 2, 3, 4. In this group, 4 4 = 1, because the usual product 16 is equivalent to 1, which divided by 5 yields a remainder of 1. for 5 divides 16 1 = 15, denoted
Is there an answer to this question: How many group elements exist if p=5?

Answer: four group elements

Question: Animals are also involved in the distribution of seeds. Fruit, which is formed by the enlargement of flower parts, is frequently a seed-dispersal tool that attracts animals to eat or otherwise disturb it, incidentally scattering the seeds it contains (see frugivory). Although many such mutualistic relationships remain too fragile to survive competition and to spread widely, flowering proved to be an unusually effective means of reproduction, spreading (whatever its origin) to become the dominant form of land plant life.
Is there an answer to this question: How does a plant benefit from competition?

Answer:
unanswerable