Problem: Capacitor:

Electrolytic capacitors use an aluminum or tantalum plate with an oxide dielectric layer. The second electrode is a liquid electrolyte, connected to the circuit by another foil plate. Electrolytic capacitors offer very high capacitance but suffer from poor tolerances, high instability, gradual loss of capacitance especially when subjected to heat, and high leakage current. Poor quality capacitors may leak electrolyte, which is harmful to printed circuit boards. The conductivity of the electrolyte drops at low temperatures, which increases equivalent series resistance. While widely used for power-supply conditioning, poor high-frequency characteristics make them unsuitable for many applications. Electrolytic capacitors will self-degrade if unused for a period (around a year), and when full power is applied may short circuit, permanently damaging the capacitor and usually blowing a fuse or causing failure of rectifier diodes (for instance, in older equipment, arcing in rectifier tubes). They can be restored before use (and damage) by gradually applying the operating voltage, often done on antique vacuum tube equipment over a period of 30 minutes by using a variable transformer to supply AC power. Unfortunately, the use of this technique may be less satisfactory for some solid state equipment, which may be damaged by operation below its normal power range, requiring that the power supply first be isolated from the consuming circuits. Such remedies may not be applicable to modern high-frequency power supplies as these produce full output voltage even with reduced input.

What is one type of metal which the conducting plates in electrolytic capacitors are never made of?
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A: unanswerable

Problem: Philosophy of space and time:

One recent proponent of the laws solution is Tim Maudlin who argues that the fundamental laws of physics are laws of temporal evolution (see Maudlin ). However, elsewhere Maudlin argues: "[the] passage of time is an intrinsic asymmetry in the temporal structure of the world... It is the asymmetry that grounds the distinction between sequences that runs from past to future and sequences which run from future to past" [ibid, 2010 edition, p. 108]. Thus it is arguably difficult to assess whether Maudlin is suggesting that the direction of time is a consequence of the laws or is itself primitive.

What does Maudlin claim time is not in the structure of the world?
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A: unanswerable

Problem: Alfred North Whitehead:

Alfred North Whitehead was born in Ramsgate, Kent, England, in 1861. His father, Alfred Whitehead, was a minister and schoolmaster of Chatham House Academy, a successful school for boys established by Thomas Whitehead, Alfred North's grandfather. Whitehead himself recalled both of them as being very successful schoolmasters, but that his grandfather was the more extraordinary man. Whitehead's mother was Maria Sarah Whitehead, formerly Maria Sarah Buckmaster. Whitehead was apparently not particularly close with his mother, as he never mentioned her in any of his writings, and there is evidence that Whitehead's wife, Evelyn, had a low opinion of her.

Who was Whitehead's aunt?
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A: unanswerable

Problem: Hard rock:

Hard rock entered the 1990s as one of the dominant forms of commercial music. The multi-platinum releases of AC/DC's The Razors Edge (1990), Guns N' Roses' Use Your Illusion I and Use Your Illusion II (both in 1991), Ozzy Osbourne's No More Tears (1991), and Van Halen's For Unlawful Carnal Knowledge (1991) showcased this popularity. Additionally, The Black Crowes released their debut album, Shake Your Money Maker (1990), which contained a bluesy classic rock sound and sold five million copies. In 1992, Def Leppard followed up 1987's Hysteria with Adrenalize, which went multi-platinum, spawned four Top 40 singles and held the number one spot on the US album chart for five weeks.

In which decade did hard rock see a decline of dominance in commercial music?
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A:
unanswerable