Problem: Transistor:

Providing sufficient base drive current is a key problem in the use of bipolar transistors as switches. The transistor provides current gain, allowing a relatively large current in the collector to be switched by a much smaller current into the base terminal. The ratio of these currents varies depending on the type of transistor, and even for a particular type, varies depending on the collector current. In the example light-switch circuit shown, the resistor is chosen to provide enough base current to ensure the transistor will be saturated.

What controls how much gain a transistor provides?
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A: unanswerable


Problem: Dialect:

The most common, and most purely linguistic, criterion is that of mutual intelligibility: two varieties are said to be dialects of the same language if being a speaker of one variety confers sufficient knowledge to understand and be understood by a speaker of the other; otherwise, they are said to be different languages. However, this definition becomes problematic in the case of dialect continua, in which it may be the case that dialect B is mutually intelligible with both dialect A and dialect C but dialects A and C are not mutually intelligible with each other. In this case the criterion of mutual intelligibility makes it impossible to decide whether A and C are dialects of the same language or not. Cases may also arise in which a speaker of dialect X can understand a speaker of dialect Y, but not vice versa; the mutual intelligibility criterion flounders here as well.

What is the definition of mutual intelligibility?
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A: if being a speaker of one variety confers sufficient knowledge to understand and be understood by a speaker of the other


Problem: Uranium:

The discovery and isolation of radium in uranium ore (pitchblende) by Marie Curie sparked the development of uranium mining to extract the radium, which was used to make glow-in-the-dark paints for clock and aircraft dials. This left a prodigious quantity of uranium as a waste product, since it takes three tonnes of uranium to extract one gram of radium. This waste product was diverted to the glazing industry, making uranium glazes very inexpensive and abundant. Besides the pottery glazes, uranium tile glazes accounted for the bulk of the use, including common bathroom and kitchen tiles which can be produced in green, yellow, mauve, black, blue, red and other colors.

Along with red, blue, black, yellow and green, what wasn't a notable color of uranium tile glaze?
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A: unanswerable


Problem: Galicia (Spain):

The interior of Galicia is characterized by its hilly landscape, although mountain ranges rise to 2,000 m (6,600 ft) in the east and south. The coastal areas are mostly an alternate series of rías (submerged valleys where the sea penetrates tens of kilometres inland) and cliffs. The climate of Galicia is temperate and rainy, but it is also markedly drier in the summer, being usually classified as Oceanic in the west and north, and Mediterranean in the southeast. Its topographic and climatic conditions have made animal husbandry and farming the primary source of Galicia's wealth for most of its history. With the exception of shipbuilding and food processing, Galicia was largely a semi-subsistence farming and fishing economy and did not experience significant industrialization until after the mid-20th century. In 2012, the gross domestic product at purchasing power parity was €56,000 million, with a nominal GDP per capita of €20,700. The population is largely concentrated in two coastal areas: from Ferrol to A Coruña in the northwest and from Pontevedra to Vigo in the southwest. To a lesser extent, there are smaller populations around the interior cities of Lugo, Ourense and Santiago de Compostela. The political capital is Santiago de Compostela, in the province of A Coruña. Vigo, in the province of Pontevedra, is the most populous municipality with 294,997 (2014), while A Coruña is the most populous city with 215.227 (2014).

Name its northwestern coastal area.
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A:
Ferrol to A Coruña