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Coats of arms were very important to the Polish nobility. Its heraldic system evolved together with its neighbours in Central Europe, while differing in many ways from the heraldry of other European countries. Polish knighthood families had its counterparts, links or roots in Moravia (i.e. Poraj) and Germany (i.e. Junosza).
Where did polish knightshood originate?
A: Moravia (i.e. Poraj) and Germany

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The nickel hydrogen battery was used for the first time in 1977 aboard the U.S. Navy's Navigation technology satellite-2 (NTS-2). For example, the ISS, Mars Odyssey and the Mars Global Surveyor are equipped with nickel-hydrogen batteries. In the dark part of its orbit, the Hubble Space Telescope is also powered by nickel-hydrogen batteries, which were finally replaced in May 2009, more than 19 years after launch, and 13 years over their design life.
What year was the first nickel hydrogen battery used?
A: 1977

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Because the spring equinox was tied to the date of Easter, the Roman Catholic Church considered the seasonal drift in the date of Easter undesirable. The Church of Alexandria celebrated Easter on the Sunday after the 14th day of the moon (computed using the Metonic cycle) that falls on or after the vernal equinox, which they placed on 21 March. However, the Church of Rome still regarded 25 March as the equinox (until 342) and used a different cycle to compute the day of the moon. In the Alexandrian system, since the 14th day of the Easter moon could fall at earliest on 21 March its first day could fall no earlier than 8 March and no later than 5 April. This meant that Easter varied between 22 March and 25 April. In Rome, Easter was not allowed to fall later than 21 April, that being the day of the Parilia or birthday of Rome and a pagan festival.The first day of the Easter moon could fall no earlier than 5 March and no later than 2 April.
What did the Church of Alexandria use to calculate the date of Easter?
A: Metonic cycle

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Honorary knighthoods are appointed to citizens of nations where Queen Elizabeth II is not Head of State, and may permit use of post-nominal letters but not the title of Sir or Dame. Occasionally honorary appointees are, incorrectly, referred to as Sir or Dame - Bill Gates or Bob Geldof, for example. Honorary appointees who later become a citizen of a Commonwealth realm can convert their appointment from honorary to substantive, then enjoy all privileges of membership of the order including use of the title of Sir and Dame for the senior two ranks of the Order. An example is Irish broadcaster Terry Wogan, who was appointed an honorary Knight Commander of the Order in 2005 and on successful application for dual British and Irish citizenship was made a substantive member and subsequently styled as "Sir Terry Wogan KBE".
Where was Queen Elizabeth ll not Head of State?
A:
citizens of nations