Problem: Paper:

Paper made from wood pulp is not necessarily less durable than a rag paper. The ageing behavior of a paper is determined by its manufacture, not the original source of the fibres. Furthermore, tests sponsored by the Library of Congress prove that all paper is at risk of acid decay, because cellulose itself produces formic, acetic, lactic and oxalic acids.

What is determined by the ageing behavior of paper?
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A: unanswerable


Problem: At the end of the last ice age, what are now the British Isles were joined to the European mainland as a mass of land extending north west from the modern-day northern coastline of France, Belgium and the Netherlands. Ice covered almost all of what is now Scotland, most of Ireland and Wales, and the hills of northern England. From 14,000 to 10,000 years ago, as the ice melted, sea levels rose separating Ireland from Great Britain and also creating the Isle of Man. About two to four millennia later, Great Britain became separated from the mainland. Britain probably became repopulated with people before the ice age ended and certainly before it became separated from the mainland. It is likely that Ireland became settled by sea after it had already become an island.
What happened to British Isles area when the ice melted after the last ice age?
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Answer: sea levels rose


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The jurisdictions of the city's administrative agencies are, in ascending order of size: the Hyderabad Police area, Hyderabad district, the GHMC area ("Hyderabad city") and the area under the Hyderabad Metropolitan Development Authority (HMDA). The HMDA is an apolitical urban planning agency that covers the GHMC and its suburbs, extending to 54 mandals in five districts encircling the city. It coordinates the development activities of GHMC and suburban municipalities and manages the administration of bodies such as the Hyderabad Metropolitan Water Supply and Sewerage Board (HMWSSB).
What does the acronym HMDA stand for?
A: Hyderabad Metropolitan Development Authority


Context and question: Other types of lossy compressors, such as the linear predictive coding (LPC) used with speech, are source-based coders. These coders use a model of the sound's generator (such as the human vocal tract with LPC) to whiten the audio signal (i.e., flatten its spectrum) before quantization. LPC may be thought of as a basic perceptual coding technique: reconstruction of an audio signal using a linear predictor shapes the coder's quantization noise into the spectrum of the target signal, partially masking it.
What does reconstruction of an audio signal shape the coder's compressor noise into?
Answer: unanswerable


Question: Another significant change undergone by many of these newly agrarian communities was one of diet. Pre-agrarian diets varied by region, season, available local plant and animal resources and degree of pastoralism and hunting. Post-agrarian diet was restricted to a limited package of successfully cultivated cereal grains, plants and to a variable extent domesticated animals and animal products. Supplementation of diet by hunting and gathering was to variable degrees precluded by the increase in population above the carrying capacity of the land and a high sedentary local population concentration. In some cultures, there would have been a significant shift toward increased starch and plant protein. The relative nutritional benefits and drawbacks of these dietary changes and their overall impact on early societal development is still debated.
Is there an answer to this question: What forced the need to supplement food supply with nutrition?

Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Brain tissue consumes a large amount of energy in proportion to its volume, so large brains place severe metabolic demands on animals. The need to limit body weight in order, for example, to fly, has apparently led to selection for a reduction of brain size in some species, such as bats. Most of the brain's energy consumption goes into sustaining the electric charge (membrane potential) of neurons. Most vertebrate species devote between 2% and 8% of basal metabolism to the brain. In primates, however, the percentage is much higher—in humans it rises to 20–25%. The energy consumption of the brain does not vary greatly over time, but active regions of the cerebral cortex consume somewhat more energy than inactive regions; this forms the basis for the functional brain imaging methods PET, fMRI, and NIRS. The brain typically gets most of its energy from oxygen-dependent metabolism of glucose (i.e., blood sugar), but ketones provide a major alternative source, together with contributions from medium chain fatty acids (caprylic and heptanoic acids), lactate, acetate, and possibly amino acids.
Where does the brain usually get most of its energy from inside the body?
A:
glucose (i.e., blood sugar