Problem: Hellenistic period:

Medicine, which was dominated by the Hippocratic tradition, saw new advances under Praxagoras of Kos, who theorized that blood traveled through the veins. Herophilos (335–280 BC) was the first to base his conclusions on dissection of the human body, animal vivisection and to provide accurate descriptions of the nervous system, liver and other key organs. Inﬂuenced by Philinus of Cos (ﬂ. 250), a student of Herophilos, a new medical sect emerged, the Empiric school, which was based on strict observation and rejected unseen causes of the Dogmatic school.

Which school of medicine was based on strict observation?
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A: Empiric


Problem: Anti-aircraft warfare:

The most extreme case was the Soviet Union, and this model may still be followed in some countries: it was a separate service, on a par with the navy or ground force. In the Soviet Union this was called Voyska PVO, and had both fighter aircraft and ground-based systems. This was divided into two arms, PVO Strany, the Strategic Air defence Service responsible for Air Defence of the Homeland, created in 1941 and becoming an independent service in 1954, and PVO SV, Air Defence of the Ground Forces. Subsequently these became part of the air force and ground forces respectively

Which country had the most severe case?
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A: Soviet Union


Problem: Financial crisis of 2007%E2%80%9308:

A cover story in BusinessWeek magazine claims that economists mostly failed to predict the worst international economic crisis since the Great Depression of the 1930s. The Wharton School of the University of Pennsylvania's online business journal examines why economists failed to predict a major global financial crisis. Popular articles published in the mass media have led the general public to believe that the majority of economists have failed in their obligation to predict the financial crisis. For example, an article in the New York Times informs that economist Nouriel Roubini warned of such crisis as early as September 2006, and the article goes on to state that the profession of economics is bad at predicting recessions. According to The Guardian, Roubini was ridiculed for predicting a collapse of the housing market and worldwide recession, while The New York Times labelled him "Dr. Doom".

What was economist Roubini called by the New York Times for predicting a collapse of the housing market?
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A: "Dr. Doom"


Problem: Bacteria:

Even more complex morphological changes are sometimes possible. For example, when starved of amino acids, Myxobacteria detect surrounding cells in a process known as quorum sensing, migrate toward each other, and aggregate to form fruiting bodies up to 500 micrometres long and containing approximately 100,000 bacterial cells. In these fruiting bodies, the bacteria perform separate tasks; this type of cooperation is a simple type of multicellular organisation. For example, about one in 10 cells migrate to the top of these fruiting bodies and differentiate into a specialised dormant state called myxospores, which are more resistant to drying and other adverse environmental conditions than are ordinary cells.

What is the vital nutriment for Myxobacteria?
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A:
amino acids