This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Q: Passage: In New York City in 1846, Alexander Turney Stewart established the "Marble Palace" on Broadway, between Chambers and Reade streets. He offered European retail merchandise at fixed prices on a variety of dry goods, and advertised a policy of providing "free entrance" to all potential customers. Though it was clad in white marble to look like a Renaissance palazzo, the building's cast iron construction permitted large plate glass windows that permitted major seasonal displays, especially in the Christmas shopping season. In 1862, Stewart built a new store on a full city block with eight floors and nineteen departments of dress goods and furnishing materials, carpets, glass and china, toys and sports equipment, ranged around a central glass-covered court. His innovations included buying from manufacturers for cash and in large quantities, keeping his markup small and prices low, truthful presentation of merchandise, the one-price policy (so there was no haggling), simple merchandise returns and cash refund policy, selling for cash and not credit, buyers who searched worldwide for quality merchandise, departmentalization, vertical and horizontal integration, volume sales, and free services for customers such as waiting rooms and free delivery of purchases. His innovations were quickly copied by other department stores. Question: What policy did the Marble Palace introduce?

A: "free entrance" to all potential customers.
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Q: Passage: The Treaty of Paris stood until 1871, when France was defeated by Prussia in the Franco-Prussian War of 18701871. While Prussia and several other German states united to form a powerful German Empire, the Emperor of the French, Napoleon III, was deposed to permit the formation of a Third French Republic. During his reign, Napoleon III, eager for the support of the United Kingdom, had opposed Russia over the Eastern Question. Russian interference in the Ottoman Empire, however, did not in any significant manner threaten the interests of France. Thus, France abandoned its opposition to Russia after the establishment of a republic. Encouraged by the decision of the French, and supported by the German minister Otto von Bismarck, Russia renounced the Black Sea clauses of the treaty agreed to in 1856. As the United Kingdom alone could not enforce the clauses, Russia once again established a fleet in the Black Sea. Question: Between what years did the Franco-Prussian War take place?

A: 18701871
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Q: Passage: SL Benfica, FC Porto, and Sporting CP are the largest sports clubs by popularity and by number of trophies won, often known as "os tres grandes" ("the big three"). They have won eight titles in the European UEFA club competitions, were present in many finals and have been regular contenders in the last stages almost every season. Other than football, many Portuguese sports clubs, including the "big three", compete in several other sports events with a varying level of success and popularity, these may include roller hockey, basketball, futsal, handball, and volleyball. The Portuguese Football Federation (FPF) Federacao Portuguesa de Futebol annually hosts the Algarve Cup, a prestigious women's football tournament that has been celebrated in the Algarvian part of Portugal. Question: What are the three largest sports clubs by popularity in Portugal?

A:
SL Benfica, FC Porto, and Sporting CP
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