Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
From the early 16th century, both Western Armenia and Eastern Armenia fell under Iranian Safavid rule. Owing to the century long Turco-Iranian geo-political rivalry that would last in Western Asia, significant parts of the region were frequently fought over between the two rivalling empires. From the mid 16th century with the Peace of Amasya, and decisively from the first half of the 17th century with the Treaty of Zuhab until the first half of the 19th century, Eastern Armenia was ruled by the successive Iranian Safavid, Afsharid and Qajar empires, while Western Armenia remained under Ottoman rule. In the late 1820s, the parts of historic Armenia under Iranian control centering on Yerevan and Lake Sevan (all of Eastern Armenia) were incorporated into the Russian Empire following Iran's forced ceding of the territories after its loss in the Russo-Persian War (1826-1828) and the outcoming Treaty of Turkmenchay. Western Armenia however, remained in Ottoman hands.
When did parts of Armenia under Iranian control become part of Russia?
A: In the late 1820s

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While successful predation results in a gain of energy, hunting invariably involves energetic costs as well. When hunger is not an issue, in general most predators will not seek to attack prey since the costs outweigh the benefits. For instance, a large predatory fish like a shark that is well fed in an aquarium will typically ignore the smaller fish swimming around it (while the prey fish take advantage of the fact that the apex predator is apparently uninterested). Surplus killing represents a deviation from this type of behaviour. The treatment of consumption in terms of cost-benefit analysis is known as optimal foraging theory, and has been quite successful in the study of animal behavior. In general, costs and benefits are considered in energy gain per unit time, though other factors are also important, such as essential nutrients that have no caloric value but are necessary for survival and health.
How is the behavior of prey fish around an uninterested predator measured?
A: unanswerable

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On 12 February 1912, after rounds of negotiations, Longyu issued an imperial edict bringing about the abdication of the child emperor Puyi. This brought an end to over 2,000 years of Imperial China and began an extended period of instability of warlord factionalism. The unorganized political and economic systems combined with a widespread criticism of Chinese culture led to questioning and doubt about the future. In the 1930s, the Empire of Japan invaded Northeast China and founded Manchukuo in 1932, with Puyi, as the emperor. After the invasion by the Soviet Union, Manchukuo collapsed in 1945.
How long did Imperial China last for?
A: 2,000 years

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In terms of ship categories, Greek companies have 22.6% of the world's tankers and 16.1% of the world's bulk carriers (in dwt). An additional equivalent of 27.45% of the world's tanker dwt is on order, with another 12.7% of bulk carriers also on order. Shipping accounts for an estimated 6% of Greek GDP, employs about 160,000 people (4% of the workforce), and represents 1/3 of the country's trade deficit. Earnings from shipping amounted to €14.1 billion in 2011, while between 2000 and 2010 Greek shipping contributed a total of €140 billion (half of the country's public debt in 2009 and 3.5 times the receipts from the European Union in the period 2000–2013). The 2011 ECSA report showed that there are approximately 750 Greek shipping companies in operation.
How many Greek shipping companies were in operation in 2011?
A:
750