The problem: Answer a question about this article:
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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The answer: low-voltage transformer windings

Problem: Please answer a question about the following article about Railway electrification system:
Railways must operate at variable speeds. Until the mid 1980s this was only practical with the brush-type DC motor, although such DC can be supplied from an AC catenary via on-board electric power conversion. Since such conversion was not well developed in the late 19th century and early 20th century, most early electrified railways used DC and many still do, particularly rapid transit (subways) and trams. Speed was controlled by connecting the traction motors in various series-parallel combinations, by varying the traction motors' fields, and by inserting and removing starting resistances to limit motor current.
What is speed limit for railways?
A: variable speeds

Question: Read this and answer the question

Rare books are found in several Yale collections. The Beinecke Rare Book Library has a large collection of rare books and manuscripts. The Harvey Cushing/John Hay Whitney Medical Library includes important historical medical texts, including an impressive collection of rare books, as well as historical medical instruments. The Lewis Walpole Library contains the largest collection of 18thcentury British literary works. The Elizabethan Club, technically a private organization, makes its Elizabethan folios and first editions available to qualified researchers through Yale.

What library has a vast assortment of rare books and manuscripts?
Answer: The Beinecke Rare Book Library

Problem: Sex was used as an important element in the content and marketing the paper from the start, which Lamb believed was the most important part of his readers' lives. The first topless Page 3 model appeared on 17 November 1970, German-born Stephanie Rahn; she was tagged as a "Birthday Suit Girl" to mark the first anniversary of the relaunched Sun. A topless Page 3 model gradually became a regular fixture, and with increasingly risque poses. Both feminists and many cultural conservatives saw the pictures as pornographic and misogynistic. Lamb expressed some regret at introducing the feature, although denied it was sexist. A Conservative council in Sowerby Bridge, Yorkshire, was the first to ban the paper from its public library, shortly after Page 3 began, because of its excessive sexual content. This decision was reversed after a sustained campaign by the newspaper itself lasting 16 months, and the election of a Labour-led council in 1971.
When was the library ban reversed?
The answer is the following: 1971

Dell had long stuck by its direct sales model. Consumers had become the main drivers of PC sales in recent years, yet there had a decline in consumers purchasing PCs through the Web or on the phone, as increasing numbers were visiting consumer electronics retail stores to try out the devices first. Dell's rivals in the PC industry, HP, Gateway and Acer, had a long retail presence and so were well poised to take advantage of the consumer shift. The lack of a retail presence stymied Dell's attempts to offer consumer electronics such as flat-panel TVs and MP3 players. Dell responded by experimenting with mall kiosks, plus quasi-retail stores in Texas and New York.
What was one city that Dell tested retail stores in?
Texas

Here is a question about this article: Apollo 11 left lunar orbit and returned to Earth, landing safely in the Pacific Ocean on July 24, 1969. When the spacecraft splashed down, 2,982 days had passed since Kennedy's commitment to landing a man on the Moon and returning him safely to the Earth before the end of the decade; the mission was completed with 161 days to spare. With the safe completion of the Apollo 11 mission, the Americans won the race to the Moon.
What is the answer to this question: When did the Apollo 11 mission land back on Earth?
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So...
July 24, 1969