Input: Read this: The earthquake also provided opportunities for researchers to retrofit data in order to model future earthquake predictions. Using data from the Intermagnet Lanzhou geomagnetic observatory, geologists Lazo Pekevski from the Ss. Cyril and Methodius University of Skopje in Macedonia and Strachimir Mavrodiev from the Bulgarian Academy of Sciences attempted to establish a "time prediction method" through collecting statistics on geomagnetism with tidal gravitational potential. Using this method, they were said to have predicted the time of the 2008 Sichuan earthquake with an accuracy of 1 day. The same study, however, acknowledges the limitation of earthquake prediction models, and does not mention that the location of the quake could be accurately predicted.
Question: What did they collect to use in this method?

Output: statistics

Input: Read this: In May 1845, the Baptist congregations in the United States split over slavery and missions. The Home Mission Society prevented slaveholders from being appointed as missionaries. The split created the Southern Baptist Convention, while the northern congregations formed their own umbrella organization now called the American Baptist Churches USA (ABC-USA). The Methodist Episcopal Church, South had recently separated over the issue of slavery, and southern Presbyterians would do so shortly thereafter.
Question: When did Baptist congregations combine efforts over slavery?

Output: unanswerable

Input: Read this: Mining was important in Thuringia since the later Middle Ages, especially within the mining towns of the Thuringian Forest such as Schmalkalden, Suhl and Ilmenau. Following the industrial revolution, the old iron, copper and silver mines declined because the competition from imported metal was too strong. On the other hand, the late 19th century brought new types of mines to Thuringia: the lignite surface mining around Meuselwitz near Altenburg in the east of the Land started in the 1870s, and two potash mining districts were established around 1900. These are the Sudharzrevier in the north of the state, between Bischofferode in the west and Roleben in the east with Sondershausen at its centre, and the Werrarevier on the Hessian border around Vacha and Bad Salzungen in the west. Together, they accounted for a significant part of the world's potash production in the mid-20th century. After the reunification, the Sudharzrevier was abandoned, whereas K+S took over the mines in the Werrarevier. Between 1950 and 1990, uranium mining was also important to cover the Soviet Union's need for this metal. The centre was Ronneburg near Gera in eastern Thuringia and the operating company Wismut was under direct Soviet control.
Question: Which towns in Thuringia are falsely known as mining towns?

Output: unanswerable

Input: Read this: As mayor, Young sought to revive the city by seeking to increase investment in the city's declining downtown. The Renaissance Center, a mixed-use office and retail complex, opened in 1977. This group of skyscrapers was an attempt to keep businesses in downtown. Young also gave city support to other large developments to attract middle and upper-class residents back to the city. Despite the Renaissance Center and other projects, the downtown area continued to lose businesses to the suburbs. Major stores and hotels closed and many large office buildings went vacant. Young was criticized for being too focused on downtown development and not doing enough to lower the city's high crime rate and improve city services.
Question: What group of buildings opened in 1977?

Output:
The Renaissance Center