Problem: American Idol:

The eligible age-range for contestants is currently fifteen to twenty-eight years old. The initial age limit was sixteen to twenty-four in the first three seasons, but the upper limit was raised to twenty-eight in season four, and the lower limit was reduced to fifteen in season ten. The contestants must be legal U.S. residents, cannot have advanced to particular stages of the competition in previous seasons (varies depending on the season, currently by the semi-final stage until season thirteen), and must not hold any current recording or talent representation contract by the semi-final stage (in previous years by the audition stage).

What is the upper age limit for contestants on American Idol?
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A: twenty-eight


Problem: Through most of Shell's early history, the Shell Oil Company business in the United States was substantially independent with its stock being traded on the NYSE and with little direct involvement from the group's central offices in the running of the American business. However, in 1984, Royal Dutch Shell made a bid to purchase those shares of Shell Oil Company it did not own (around 30%) and despite opposition from some minority shareholders, which led to a court case, Shell completed the buyout for a sum of $5.7 billion.
Shell Oil Company's United States business throughout its early history is described as what?
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Answer: substantially independent


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Particularly since the mid-1960s there have been advances in understanding of the physics of plant physiological processes such as transpiration (the transport of water within plant tissues), the temperature dependence of rates of water evaporation from the leaf surface and the molecular diffusion of water vapour and carbon dioxide through stomatal apertures. These developments, coupled with new methods for measuring the size of stomatal apertures, and the rate of photosynthesis have enabled precise description of the rates of gas exchange between plants and the atmosphere. Innovations in statistical analysis by Ronald Fisher, Frank Yates and others at Rothamsted Experimental Station facilitated rational experimental design and data analysis in botanical research. The discovery and identification of the auxin plant hormones by Kenneth V. Thimann in 1948 enabled regulation of plant growth by externally applied chemicals. Frederick Campion Steward pioneered techniques of micropropagation and plant tissue culture controlled by plant hormones. The synthetic auxin 2,4-Dichlorophenoxyacetic acid or 2,4-D was one of the first commercial synthetic herbicides.
What can auxin plant hormones also be used as?
A: herbicides


Context and question: The Early Cretaceous spans from 145 million to 100 million years ago. The Early Cretaceous saw the expansion of seaways, and as a result, the decline and extinction of sauropods (except in South America). Many coastal shallows were created, and that caused Ichthyosaurs to die out. Mosasaurs evolved to replace them as head of the seas. Some island-hopping dinosaurs, like Eustreptospondylus, evolved to cope with the coastal shallows and small islands of ancient Europe. Other dinosaurs rose up to fill the empty space that the Jurassic-Cretaceous extinction left behind, such as Carcharodontosaurus and Spinosaurus. Of the most successful would be the Iguanodon which spread to every continent. Seasons came back into effect and the poles got seasonally colder, but dinosaurs still inhabited this area like the Leaellynasaura which inhabited the polar forests year-round, and many dinosaurs migrated there during summer like Muttaburrasaurus. Since it was too cold for crocodiles, it was the last stronghold for large amphibians, like Koolasuchus. Pterosaurs got larger as species like Tapejara and Ornithocheirus evolved.
What caused Ichthyosaurs to thrive?
Answer: unanswerable


Question: The hourglass uses the flow of sand to measure the flow of time. They were used in navigation. Ferdinand Magellan used 18 glasses on each ship for his circumnavigation of the globe (1522). Incense sticks and candles were, and are, commonly used to measure time in temples and churches across the globe. Waterclocks, and later, mechanical clocks, were used to mark the events of the abbeys and monasteries of the Middle Ages. Richard of Wallingford (1292–1336), abbot of St. Alban's abbey, famously built a mechanical clock as an astronomical orrery about 1330. Great advances in accurate time-keeping were made by Galileo Galilei and especially Christiaan Huygens with the invention of pendulum driven clocks along with the invention of the minute hand by Jost Burgi.
Is there an answer to this question: How many inventions were made by Galileo?

Answer: unanswerable


Problem: Kievan Rus%27:

From the 9th century, the Pecheneg nomads began an uneasy relationship with Kievan Rus′. For over two centuries they launched sporadic raids into the lands of Rus′, which sometimes escalated into full-scale wars (such as the 920 war on the Pechenegs by Igor of Kiev reported in the Primary Chronicle), but there were also temporary military alliances (e.g. the 943 Byzantine campaign by Igor). In 968, the Pechenegs attacked and besieged the city of Kiev. Some speculation exists that the Pechenegs drove off the Tivertsi and the Ulichs to the regions of the upper Dniester river in Bukovina. The Byzantine Empire was known to support the Pechenegs in their military campaigns against the Eastern Slavic states.[citation needed]

What did the Pecheneg frequently not do over the span of two centuries?
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A:
unanswerable