Problem: Northwestern University:

Northwestern was founded in 1851 by John Evans, for whom the City of Evanston is named, and eight other lawyers, businessmen and Methodist leaders. Its founding purpose was to serve the Northwest Territory, an area that today includes the states of Ohio, Indiana, Illinois, Michigan, Wisconsin and parts of Minnesota. Instruction began in 1855; women were admitted in 1869. Today, the main campus is a 240-acre (97 ha) parcel in Evanston, along the shores of Lake Michigan just 12 miles north of downtown Chicago. The university's law, medical, and professional schools are located on a 25-acre (10 ha) campus in Chicago's Streeterville neighborhood. In 2008, the university opened a campus in Education City, Doha, Qatar with programs in journalism and communication.

Which great lake is Northwestern located along?
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A: Lake Michigan

Problem: The fortified city temporarily fell to the French invasion in 1672 (the Disaster Year); where the French invasion was only stopped west of Utrecht at the Old Hollandic Waterline. In 1674, only two years after the French left, the centre of Utrecht was struck by a tornado. The halt to building before construction of flying buttresses in the 15th century now proved to be the undoing of the central section of the cathedral of St Martin church which collapsed; creating the current Dom square between the tower and choir. In 1713, Utrecht hosted one of the first international peace negotiations when the Treaty of Utrecht settled the War of the Spanish Succession. Since 1723 Utrecht became the centre of the non-Roman Old Catholic Churches in the world.
Since 1723 what has Utrecht become
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Answer: Utrecht became the centre of the non-Roman Old Catholic Churches in the world

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The ReWritable Audio CD is designed to be used in a consumer audio CD recorder, which will not (without modification) accept standard CD-RW discs. These consumer audio CD recorders use the Serial Copy Management System (SCMS), an early form of digital rights management (DRM), to conform to the United States' Audio Home Recording Act (AHRA). The ReWritable Audio CD is typically somewhat more expensive than CD-RW due to (a) lower volume and (b) a 3% AHRA royalty used to compensate the music industry for the making of a copy.
Why is the CD-RW more expensive than the ReWritable CD?
A: unanswerable

Context and question: Located in the American South, Houston is a diverse city with a large and growing international community. The metropolitan area is home to an estimated 1.1 million (21.4 percent) residents who were born outside the United States, with nearly two-thirds of the area's foreign-born population from south of the United StatesMexico border. Additionally, more than one in five foreign-born residents are from Asia. The city is home to the nation's third-largest concentration of consular offices, representing 86 countries.
How many foreign born Houstonites are from Asia?
Answer: one in five

Question: The term "great power" was first used to represent the most important powers in Europe during the post-Napoleonic era. The "Great Powers" constituted the "Concert of Europe" and claimed the right to joint enforcement of the postwar treaties. The formalization of the division between small powers and great powers came about with the signing of the Treaty of Chaumont in 1814. Since then, the international balance of power has shifted numerous times, most dramatically during World War I and World War II. While some nations are widely considered to be great powers, there is no definitive list of them. In literature, alternative terms for great power are often world power or major power, but these terms can also be interchangeable with superpower.
Is there an answer to this question: During the post Napoleonic era where were the first Great Powers concentrated?

Answer: Europe

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
At low frequencies (such as AM broadcast), arrays of vertical towers are used to achieve directionality and they will occupy large areas of land. For reception, a long Beverage antenna can have significant directivity. For non directional portable use, a short vertical antenna or small loop antenna works well, with the main design challenge being that of impedance matching. With a vertical antenna a loading coil at the base of the antenna may be employed to cancel the reactive component of impedance; small loop antennas are tuned with parallel capacitors for this purpose.
For radio broadcast that one would hear in their car what type of towers are used?
A:
vertical