Input: Read this: As the 10th century progressed, the Khazars were no longer able to command tribute from the Volga Bulgars, and their relationship with the Byzantines deteriorated, as Byzantium increasingly allied with the Pechenegs against them. The Pechenegs were thus secure to raid the lands of the Khazars from their base between the Volga and Don rivers, allowing them to expand to the west. Rus' relations with the Pechenegs were complex, as the groups alternately formed alliances with and against one another. The Pechenegs were nomads roaming the steppe raising livestock which they traded with the Rus' for agricultural goods and other products. The lucrative Rus' trade with the Byzantine Empire had to pass through Pecheneg-controlled territory, so the need for generally peaceful relations was essential. Nevertheless, while the Primary Chronicle reports the Pechenegs entering Rus' territory in 915 and then making peace, they were waging war with one another again in 920. Pechenegs are reported assisting the Rus' in later campaigns against the Byzantines, yet allied with the Byzantines against the Rus' at other times.
Question: Around what time did the Khazars unable to no longer command tribute from Volga?

Output: 10th century


Input: Read this: Many Somerset soldiers died during the First World War, with the Somerset Light Infantry suffering nearly 5,000 casualties. War memorials were put up in most of the county's towns and villages; only nine, described as the Thankful Villages, had none of their residents killed. During the Second World War the county was a base for troops preparing for the D-Day landings. Some of the hospitals which were built for the casualties of the war remain in use. The Taunton Stop Line was set up to repel a potential German invasion. The remains of its pill boxes can still be seen along the coast, and south through Ilminster and Chard.
Question: What was one of the Thankful Villages?

Output: unanswerable


Input: Read this: In 1996, Marvel had some of its titles participate in "Heroes Reborn", a crossover that allowed Marvel to relaunch some of its flagship characters such as the Avengers and the Fantastic Four, and outsource them to the studios of two of the former Marvel artists turned Image Comics founders, Jim Lee and Rob Liefeld. The relaunched titles, which saw the characters transported to a parallel universe with a history distinct from the mainstream Marvel Universe, were a solid success amidst a generally struggling industry, but Marvel discontinued the experiment after a one-year run and returned the characters to the Marvel Universe proper. In 1998, the company launched the imprint Marvel Knights, taking place within Marvel continuity; helmed by soon-to-become editor-in-chief Joe Quesada, it featured tough, gritty stories showcasing such characters as the Inhumans, Black Panther and Daredevil.
Question: What year did Joe Quesada become editor in chief?

Output: unanswerable


Input: Read this: Lester Brown states that the market "does not incorporate the indirect costs of providing goods or services into prices, it does not value nature's services adequately, and it does not respect the sustainable-yield thresholds of natural systems". It also favors the near term over the long term, thereby showing limited concern for future generations. Tax and subsidy shifting can help overcome these problems, though is also problematic to combine different international normative regimes regulating this issue.
Question:  Lester Brown states that the market incorporates what?

Output:
unanswerable