Problem: Mexico City:

In addition, the city has about 160 museumsthe world's greatest single metropolitan concentration over 100 art galleries, and some 30 concert halls, all of which maintain a constant cultural activity during the whole year. It has either the third or fourth-highest number of theatres in the world after New York, London and perhaps Toronto. Many areas (e.g. Palacio Nacional and the National Institute of Cardiology) have murals painted by Diego Rivera. He and his wife Frida Kahlo lived in Coyoacan, where several of their homes, studios, and art collections are open to the public. The house where Leon Trotsky was initially granted asylum and finally murdered in 1940 is also in Coyoacan.

How many concert halls are in Mexico City?
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A: 30

Problem: Geological history of Earth:

The Silurian is a major division of the geologic timescale that started about 443.8 1.5 Ma. During the Silurian, Gondwana continued a slow southward drift to high southern latitudes, but there is evidence that the Silurian ice caps were less extensive than those of the late Ordovician glaciation. The melting of ice caps and glaciers contributed to a rise in sea levels, recognizable from the fact that Silurian sediments overlie eroded Ordovician sediments, forming an unconformity. Other cratons and continent fragments drifted together near the equator, starting the formation of a second supercontinent known as Euramerica. The vast ocean of Panthalassa covered most of the northern hemisphere. Other minor oceans include Proto-Tethys, Paleo-Tethys, Rheic Ocean, a seaway of Iapetus Ocean (now in between Avalonia and Laurentia), and newly formed Ural Ocean.

What did the melting of ice on Gondwana add to?
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A: a rise in sea levels

Problem: Clothing:

In past times, mending was an art. A meticulous tailor or seamstress could mend rips with thread raveled from hems and seam edges so skillfully that the tear was practically invisible. When the raw material cloth was worth more than labor, it made sense to expend labor in saving it. Today clothing is considered a consumable item. Mass-manufactured clothing is less expensive than the labor required to repair it. Many people buy a new piece of clothing rather than spend time mending. The thrifty still replace zippers and buttons and sew up ripped hems.

What is not considered a consumable item today?
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A: unanswerable

Problem: Westminster Abbey:

The first reports of the abbey are based on a late tradition claiming that a young fisherman called Aldrich on the River Thames saw a vision of Saint Peter near the site. This seems to be quoted to justify the gifts of salmon from Thames fishermen that the abbey received in later years. In the present era, the Fishmonger's Company still gives a salmon every year. The proven origins are that in the 960s or early 970s, Saint Dunstan, assisted by King Edgar, installed a community of Benedictine monks here.

Who, till this day still gives the Abbey a bun?
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A:
unanswerable