Problem: BeiDou Navigation Satellite System:

The ranging signals are based on the CDMA principle and have complex structure typical of Galileo or modernized GPS. Similar to the other GNSS, there will be two levels of positioning service: open and restricted (military). The public service shall be available globally to general users. When all the currently planned GNSS systems are deployed, the users will benefit from the use of a total constellation of 75+ satellites, which will significantly improve all the aspects of positioning, especially availability of the signals in so-called urban canyons. The general designer of the COMPASS navigation system is Sun Jiadong, who is also the general designer of its predecessor, the original BeiDou navigation system.

What positioning levels will the BeiDou system offer?
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A: open and restricted (military)


Problem: The period between 1815 and 1871 saw a large number of revolutionary attempts and independence wars. Balkan nations began to regain independence from the Ottoman Empire. Italy unified into a nation state. The capture of Rome in 1870 ended the Papal temporal power. Rivalry in a scramble for empires spread in what is known as The Age of Empire.
When were there many struggles for independence or overthrowing prevailing governments?
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Answer: between 1815 and 1871


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The Mature Indus civilisation flourished from about 2600 to 1900 BCE, marking the beginning of urban civilisation on the subcontinent. The civilisation included urban centres such as Dholavira, Kalibangan, Ropar, Rakhigarhi, and Lothal in modern-day India, as well as Harappa, Ganeriwala, and Mohenjo-daro in modern-day Pakistan. The civilisation is noted for its cities built of brick, roadside drainage system, and multistoreyed houses and is thought to have had some kind of municipal organization.
When did the Mature Indus Civilization thrive? 
A: 2600 to 1900 BCE


Context and question: In the wake of the discovery, there was much nationalistic rivalry between the French and the British over who deserved credit for the discovery. Eventually, an international consensus emerged that both Le Verrier and Adams jointly deserved credit. Since 1966, Dennis Rawlins has questioned the credibility of Adams's claim to co-discovery, and the issue was re-evaluated by historians with the return in 1998 of the "Neptune papers" (historical documents) to the Royal Observatory, Greenwich. After reviewing the documents, they suggest that "Adams does not deserve equal credit with Le Verrier for the discovery of Neptune. That credit belongs only to the person who succeeded both in predicting the planet's place and in convincing astronomers to search for it."
Who ultimately deserved credit for the discovery of Neptune? 
Answer: Le Verrier and Adams


Question: Following the successes of his trial-run games, Foster moved ahead with his idea for arena football. He founded the Arena Football League with four teams: the Pittsburgh Gladiators, Denver Dynamite, Washington Commandos, and Chicago Bruisers. Foster appointed legendary Darrel "Mouse" Davis, godfather of the "run and shoot" and modern pro offenses, as executive director of football operations. Davis hired the original coaches and was the architect of the league's original wide-open offensive playbooks.
Is there an answer to this question: What was Darrell Davis' nickname?

Answer: Mouse


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The simplest known circadian clock is that of the prokaryotic cyanobacteria. Recent research has demonstrated that the circadian clock of Synechococcus elongatus can be reconstituted in vitro with just the three proteins (KaiA, KaiB, KaiC) of their central oscillator. This clock has been shown to sustain a 22-hour rhythm over several days upon the addition of ATP. Previous explanations of the prokaryotic circadian timekeeper were dependent upon a DNA transcription/translation feedback mechanism.[citation needed]
Where can the circadian clock of theprokaryotic cyanobacteria be reconstituted?
A:
unanswerable