Problem: Capacitor:

Most types of capacitor include a dielectric spacer, which increases their capacitance. These dielectrics are most often insulators. However, low capacitance devices are available with a vacuum between their plates, which allows extremely high voltage operation and low losses. Variable capacitors with their plates open to the atmosphere were commonly used in radio tuning circuits. Later designs use polymer foil dielectric between the moving and stationary plates, with no significant air space between them.

What did the later designs of capacitors used in radio tuning circuits still have?
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A: unanswerable

Problem: A person's self-report is the most reliable measure of pain, with health care professionals tending to underestimate severity. A definition of pain widely employed in nursing, emphasizing its subjective nature and the importance of believing patient reports, was introduced by Margo McCaffery in 1968: "Pain is whatever the experiencing person says it is, existing whenever he says it does". To assess intensity, the patient may be asked to locate their pain on a scale of 0 to 10, with 0 being no pain at all, and 10 the worst pain they have ever felt. Quality can be established by having the patient complete the McGill Pain Questionnaire indicating which words best describe their pain.
What is the most reliable measure of pain?
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Answer: person's self-report

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The work of David Hilbert and Max Planck was crucial to the foundation of modern physics, which Werner Heisenberg and Erwin Schrodinger developed further. They were preceded by such key physicists as Hermann von Helmholtz, Joseph von Fraunhofer, and Gabriel Daniel Fahrenheit, among others. Wilhelm Conrad Rontgen discovered X-rays, an accomplishment that made him the first winner of the Nobel Prize in Physics in 1901. The Walhalla temple for "laudable and distinguished Germans", features a number of scientists, and is located east of Regensburg, in Bavaria.
What two people were important to the creation of modern physics?
A: David Hilbert and Max Planck

Context and question: As a result of continued warming, the polar ice caps melted and much of Gondwana became a desert. In Eastern Antarctica, seed ferns or pteridosperms became abundant and large amounts of sandstone and shale were laid down at this time. Synapsids, commonly known as "mammal-like reptiles", were common in Antarctica during the Early Triassic and included forms such as Lystrosaurus. The Antarctic Peninsula began to form during the Jurassic period (206146 Ma), and islands gradually rose out of the ocean. Ginkgo trees, conifers, bennettites, horsetails, ferns and cycads were plentiful during this period. In West Antarctica, coniferous forests dominated through the entire Cretaceous period (14666 Ma), though southern beech became more prominent towards the end of this period. Ammonites were common in the seas around Antarctica, and dinosaurs were also present, though only three Antarctic dinosaur genera (Cryolophosaurus and Glacialisaurus, from the Hanson Formation, and Antarctopelta) have been described to date. It was during this era that Gondwana began to break up.
What began to form during the years 204-166 Ma?
Answer: unanswerable

Question: The City of Charleston Police Department, with a total of 452 sworn officers, 137 civilians, and 27 reserve police officers, is South Carolina's largest police department. Their procedures on cracking down on drug use and gang violence in the city are used as models to other cities to do the same.[citation needed] According to the final 2005 FBI Crime Reports, Charleston crime level is worse than the national average in almost every major category. Greg Mullen, the former Deputy Chief of the Virginia Beach, Virginia Police Department, serves as the current Chief of the Charleston Police Department. The former Charleston police chief was Reuben Greenberg, who resigned August 12, 2005. Greenberg was credited with creating a polite police force that kept police brutality well in check, even as it developed a visible presence in community policing and a significant reduction in crime rates.
Is there an answer to this question: How many civilians serve on the Charleston Police Department?

Answer: 137

Problem: Railway electrification system:

An early advantage of AC is that the power-wasting resistors used in DC locomotives for speed control were not needed in an AC locomotive: multiple taps on the transformer can supply a range of voltages. Separate low-voltage transformer windings supply lighting and the motors driving auxiliary machinery. More recently, the development of very high power semiconductors has caused the classic "universal" AC/DC motor to be largely replaced with the three-phase induction motor fed by a variable frequency drive, a special inverter that varies both frequency and voltage to control motor speed. These drives can run equally well on DC or AC of any frequency, and many modern electric locomotives are designed to handle different supply voltages and frequencies to simplify cross-border operation.

What taps can provide lighting supply?
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A:
low-voltage transformer windings