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Charles Pollak (born Karol Pollak), the inventor of the first electrolytic capacitors, found out that the oxide layer on an aluminum anode remained stable in a neutral or alkaline electrolyte, even when the power was switched off. In 1896 he filed a patent for an "Electric liquid capacitor with aluminum electrodes." Solid electrolyte tantalum capacitors were invented by Bell Laboratories in the early 1950s as a miniaturized and more reliable low-voltage support capacitor to complement their newly invented transistor.
In what sort of electrolyte does the oxide layer on an aluminum anode remain unstable?
A: unanswerable

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Tito's estrangement from the USSR enabled Yugoslavia to obtain US aid via the Economic Cooperation Administration (ECA), the same US aid institution which administered the Marshall Plan. Still, he did not agree to align with the West, which was a common consequence of accepting American aid at the time. After Stalin's death in 1953, relations with the USSR were relaxed and he began to receive aid as well from the COMECON. In this way, Tito played East-West antagonism to his advantage. Instead of choosing sides, he was instrumental in kick-starting the Non-Aligned Movement, which would function as a 'third way' for countries interested in staying outside of the East-West divide.
Which country gave Yugoslavia aid when Tito became estranged from the USSR?
A: US

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Stretching west from the Blue Ridge for approximately 55 miles (89 km) is the Ridge and Valley region, in which numerous tributaries join to form the Tennessee River in the Tennessee Valley. This area of Tennessee is covered by fertile valleys separated by wooded ridges, such as Bays Mountain and Clinch Mountain. The western section of the Tennessee Valley, where the depressions become broader and the ridges become lower, is called the Great Valley. In this valley are numerous towns and two of the region's three urban areas, Knoxville, the 3rd largest city in the state, and Chattanooga, the 4th largest city in the state. The third urban area, the Tri-Cities, comprising Bristol, Johnson City, and Kingsport and their environs, is located to the northeast of Knoxville.
What river forms in the Tennessee Valley?
A: Tennessee River

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The relative pitches of individual notes in a scale may be determined by one of a number of tuning systems. In the west, the twelve-note chromatic scale is the most common method of organization, with equal temperament now the most widely used method of tuning that scale. In it, the pitch ratio between any two successive notes of the scale is exactly the twelfth root of two (or about 1.05946). In well-tempered systems (as used in the time of Johann Sebastian Bach, for example), different methods of musical tuning were used. Almost all of these systems have one interval in common, the octave, where the pitch of one note is double the frequency of another. For example, if the A above middle C is 440 Hz, the A an octave above that is 880 Hz (info).
All these different methods have what in common?
A:
the octave