Problem: Transistor:

FETs are further divided into depletion-mode and enhancement-mode types, depending on whether the channel is turned on or off with zero gate-to-source voltage. For enhancement mode, the channel is off at zero bias, and a gate potential can "enhance" the conduction. For the depletion mode, the channel is on at zero bias, and a gate potential (of the opposite polarity) can "deplete" the channel, reducing conduction. For either mode, a more positive gate voltage corresponds to a higher current for n-channel devices and a lower current for p-channel devices. Nearly all JFETs are depletion-mode because the diode junctions would forward bias and conduct if they were enhancement-mode devices; most IGFETs are enhancement-mode types.

At what point is a channel off in enhancement-mode?
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A: at zero bias


Problem: Tajikistan:

Tajiks began to be conscripted into the Soviet Army in 1939 and during World War II around 260,000 Tajik citizens fought against Germany, Finland and Japan. Between 60,000(4%) and 120,000(8%) of Tajikistan's 1,530,000 citizens were killed during World War II. Following the war and Stalin's reign attempts were made to further expand the agriculture and industry of Tajikistan. During 1957–58 Nikita Khrushchev's Virgin Lands Campaign focused attention on Tajikistan, where living conditions, education and industry lagged behind the other Soviet Republics. In the 1980s, Tajikistan had the lowest household saving rate in the USSR, the lowest percentage of households in the two top per capita income groups, and the lowest rate of university graduates per 1000 people. By the late 1980s Tajik nationalists were calling for increased rights. Real disturbances did not occur within the republic until 1990. The following year, the Soviet Union collapsed, and Tajikistan declared its independence.

Whose living conditions, education, and industry outpaced the other Soviet Republics?
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A: unanswerable


Problem: Computer security:

One use of the term "computer security" refers to technology that is used to implement secure operating systems. In the 1980s the United States Department of Defense (DoD) used the "Orange Book" standards, but the current international standard ISO/IEC 15408, "Common Criteria" defines a number of progressively more stringent Evaluation Assurance Levels. Many common operating systems meet the EAL4 standard of being "Methodically Designed, Tested and Reviewed", but the formal verification required for the highest levels means that they are uncommon. An example of an EAL6 ("Semiformally Verified Design and Tested") system is Integrity-178B, which is used in the Airbus A380 and several military jets.

When was the Common Criteria defined?
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A: unanswerable


Problem: Warsaw Pact:

The strategy behind the formation of the Warsaw Pact was driven by the desire of the Soviet Union to dominate Central and Eastern Europe. This policy was driven by ideological and geostrategic reasons. Ideologically, the Soviet Union arrogated the right to define socialism and communism and act as the leader of the global socialist movement. A corollary to this idea was the necessity of intervention if a country appeared to be violating core socialist ideas and Communist Party functions, which was explicitly stated in the Brezhnev Doctrine. Geostrategic principles also drove the Soviet Union to prevent invasion of its territory by Western European powers.

Who wanted to dominate Western and Eastern Europe?
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A:
unanswerable