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Film speed is found from a plot of optical density vs. log of exposure for the film, known as the D–log H curve or Hurter–Driffield curve. There typically are five regions in the curve: the base + fog, the toe, the linear region, the shoulder, and the overexposed region. For black-and-white negative film, the “speed point” m is the point on the curve where density exceeds the base + fog density by 0.1 when the negative is developed so that a point n where the log of exposure is 1.3 units greater than the exposure at point m has a density 0.8 greater than the density at point m. The exposure Hm, in lux-s, is that for point m when the specified contrast condition is satisfied. The ISO arithmetic speed is determined from:
What is denoted when the specified contrast condition is met?
A: The exposure Hm, in lux-s

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Praça dos Três Poderes (Portuguese for Square of the Three Powers) is a plaza in Brasília. The name is derived from the encounter of the three federal branches around the plaza: the Executive, represented by the Palácio do Planalto (presidential office); the Legislative, represented by the National Congress (Congresso Nacional); and the Judicial branch, represented by the Supreme Federal Court (Supremo Tribunal Federal). It is a tourist attraction in Brasília, designed by Lúcio Costa and Oscar Niemeyer as a place where the three branches would meet harmoniously.
What does 'Praça dos Três Poderes' mean?
A: Square of the Three Powers

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The Germanic peoples during the Migrations Period came into contact with other peoples; in the case of the populations settling in the territory of modern Germany, they encountered Celts to the south, and Balts and Slavs towards the east. The Limes Germanicus was breached in AD 260. Migrating Germanic tribes commingled with the local Gallo-Roman populations in what is now Swabia and Bavaria. The arrival of the Huns in Europe resulted in Hun conquest of large parts of Eastern Europe, the Huns initially were allies of the Roman Empire who fought against Germanic tribes, but later the Huns cooperated with the Germanic tribe of the Ostrogoths, and large numbers of Germans lived within the lands of the Hunnic Empire of Attila. Attila had both Hunnic and Germanic families and prominent Germanic chiefs amongst his close entourage in Europe. The Huns living in Germanic territories in Eastern Europe adopted an East Germanic language as their lingua franca. A major part of Attila's army were Germans, during the Huns' campaign against the Roman Empire. After Attila's unexpected death the Hunnic Empire collapsed with the Huns disappearing as a people in Europe – who either escaped into Asia, or otherwise blended in amongst Europeans.
Who allied with the Germans after previous fighting them along side the Romans?
A: the Huns

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His birthday (14 December 1895) was the 34th anniversary of the death of his great-grandfather, Prince Albert, the Prince Consort. Uncertain of how the Prince Consort's widow, Queen Victoria, would take the news of the birth, the Prince of Wales wrote to the Duke of York that the Queen had been "rather distressed". Two days later, he wrote again: "I really think it would gratify her if you yourself proposed the name Albert to her". Queen Victoria was mollified by the proposal to name the new baby Albert, and wrote to the Duchess of York: "I am all impatience to see the new one, born on such a sad day but rather more dear to me, especially as he will be called by that dear name which is a byword for all that is great and good". Consequently, he was baptised "Albert Frederick Arthur George" at St. Mary Magdalene's Church near Sandringham three months later.[a] As a great-grandson of Queen Victoria, he was known formally as His Highness Prince Albert of York from birth. Within the family, he was known informally as "Bertie". His maternal grandmother, the Duchess of Teck, did not like the first name the baby had been given, and she wrote prophetically that she hoped the last name "may supplant the less favoured one".
Who was the Duchess of Teck?
A:
unanswerable