The problem: Answer a question about this article:
Detroit has four border crossings: the Ambassador Bridge and the DetroitWindsor Tunnel provide motor vehicle thoroughfares, with the Michigan Central Railway Tunnel providing railroad access to and from Canada. The fourth border crossing is the DetroitWindsor Truck Ferry, located near the Windsor Salt Mine and Zug Island. Near Zug Island, the southwest part of the city was developed over a 1,500-acre (610 ha) salt mine that is 1,100 feet (340 m) below the surface. The Detroit Salt Company mine has over 100 miles (160 km) of roads within.
How many acres is the Windsor Salt Mine?
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The answer: 1,500

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The Baltic Way or Baltic Chain (also Chain of Freedom Estonian: Balti kett, Latvian: Baltijas cels, Lithuanian: Baltijos kelias, Russian: ) was a peaceful political demonstration on August 23, 1989. An estimated 2 million people joined hands to form a human chain extending 600 kilometres (370 mi) across Estonia, Latvia and Lithuania, which had been forcibly reincorporated into the Soviet Union in 1944. The colossal demonstration marked the 50th anniversary of the MolotovRibbentrop Pact that divided Eastern Europe into spheres of influence and led to the occupation of the Baltic states in 1940.
What part of Europe was split up by the pact?
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The answer: Eastern

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Chopin's etudes are largely in straightforward ternary form. He used them to teach his own technique of piano playingfor instance playing double thirds (Op. 25, No. 6), playing in octaves (Op. 25, No. 10), and playing repeated notes (Op. 10, No. 7).
What pieces of his did Chopin use to teach his technique?
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The answer: etudes

The problem: Answer a question about this article:
Interspecific crop diversity is, in part, responsible for offering variety in what we eat. Intraspecific diversity, the variety of alleles within a single species, also offers us choice in our diets. If a crop fails in a monoculture, we rely on agricultural diversity to replant the land with something new. If a wheat crop is destroyed by a pest we may plant a hardier variety of wheat the next year, relying on intraspecific diversity. We may forgo wheat production in that area and plant a different species altogether, relying on interspecific diversity. Even an agricultural society which primarily grows monocultures, relies on biodiversity at some point.
When do we rely on agricultural diversity to replant the land with something new?
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The answer:
If a crop fails in a monoculture