Here is a question about this article: The most important river in Thuringia is the Saale (a tributary of the Elbe) with its tributaries Unstrut, Ilm and Weie Elster, draining the most parts of Thuringia and the Werra (the headwater of the Weser), draining the south-west and west of the Land. Furthermore, some small parts on the southern border are drained by tributaries of the Main (a tributary of the Rhine). There are no large natural lakes in Thuringia, but it does have some of Germany's biggest dams including the Bleiloch Dam and the Hohenwarte Dam at Saale river same as the Leibis-Lichte Dam and the Goldisthal Pumped Storage Station within the Highland. Thuringia is Germany's only state without connection to navigable waterways.
What is the answer to this question: Which river in Thuringia is the most important?
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So... the Saale

Here is a question about this article: The United Nations Charter states that treaties must be registered with the UN to be invoked before it or enforced in its judiciary organ, the International Court of Justice. This was done to prevent the proliferation of secret treaties that occurred in the 19th and 20th century. Section 103 of the Charter also states that its members' obligations under it outweigh any competing obligations under other treaties.
What is the answer to this question: In which centuries did a proliferation of secret treaties occur that led the United Nations Charter to include an obligation to register treaties to be invoked before it?
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So... 19th and 20th century

Here is a question about this article: In 2003, the season expanded to 16 games. There were also several rule changes in this period. In 2005, players were no longer allowed to run out of bounds. The only way for a player to go out of bounds presently is if he is tackled into or deliberately contacts the side boards. This was also the first year the ArenaBowl was played at a neutral site. In 2007, free substitution was allowed, ending the "iron man" era of one-platoon football. And in 2008, the "jack" linebacker was allowed to go sideboard to sideboard without being penalized for "illegal defense".
What is the answer to this question: What year introduced the free substitution rule?
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So...
2007