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Two assumptions underpinned the British approach to HAA fire; first, aimed fire was the primary method and this was enabled by predicting gun data from visually tracking the target and having its height. Second, that the target would maintain a steady course, speed and height. This HAA was to engage targets up to 24,000 feet. Mechanical, as opposed to igniferous, time fuses were required because the speed of powder burning varied with height so fuse length was not a simple function of time of flight. Automated fire ensured a constant rate of fire that made it easier to predict where each shell should be individually aimed.

Another assumption was that the target would maintain a steady course along with what other two factors?
Answer: speed and height
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Following the Fall of Constantinople on 29 May 1453, many Greeks sought better employment and education opportunities by leaving for the West, particularly Italy, Central Europe, Germany and Russia. Greeks are greatly credited for the European cultural revolution, later called, the Renaissance. In Greek-inhabited territory itself, Greeks came to play a leading role in the Ottoman Empire, due in part to the fact that the central hub of the empire, politically, culturally, and socially, was based on Western Thrace and Greek Macedonia, both in Northern Greece, and of course was centred on the mainly Greek-populated, former Byzantine capital, Constantinople. As a direct consequence of this situation, Greek-speakers came to play a hugely important role in the Ottoman trading and diplomatic establishment, as well as in the church. Added to this, in the first half of the Ottoman period men of Greek origin made up a significant proportion of the Ottoman army, navy, and state bureaucracy, having been levied as adolescents (along with especially Albanians and Serbs) into Ottoman service through the devshirme. Many Ottomans of Greek (or Albanian or Serb) origin were therefore to be found within the Ottoman forces which governed the provinces, from Ottoman Egypt, to Ottomans occupied Yemen and Algeria, frequently as provincial governors.

When did the emperor Constantine  lose rule over in 1453 ?
Answer: Fall of Constantinople on 29 May 1453
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In the 1960s, Downtown Houston consisted of a collection of mid-rise office structures. Downtown was on the threshold of an energy industry–led boom in 1970. A succession of skyscrapers were built throughout the 1970s—many by real estate developer Gerald D. Hines—culminating with Houston's tallest skyscraper, the 75-floor, 1,002-foot (305 m)-tall JPMorgan Chase Tower (formerly the Texas Commerce Tower), completed in 1982. It is the tallest structure in Texas, 15th tallest building in the United States, and the 85th tallest skyscraper in the world, based on highest architectural feature. In 1983, the 71-floor, 992-foot (302 m)-tall Wells Fargo Plaza (formerly Allied Bank Plaza) was completed, becoming the second-tallest building in Houston and Texas. Based on highest architectural feature, it is the 17th tallest in the United States and the 95th tallest in the world. In 2007, downtown Houston had over 43 million square feet (4,000,000 m²) of office space.

When were skyscrapers first built in Houston?
Answer:
throughout the 1970s