Problem: Lighting:

With the discovery of fire, the earliest form of artificial lighting used to illuminate an area were campfires or torches. As early as 400,000 BCE, fire was kindled in the caves of Peking Man. Prehistoric people used primitive oil lamps to illuminate surroundings. These lamps were made from naturally occurring materials such as rocks, shells, horns and stones, were filled with grease, and had a fiber wick. Lamps typically used animal or vegetable fats as fuel. Hundreds of these lamps (hollow worked stones) have been found in the Lascaux caves in modern-day France, dating to about 15,000 years ago. Oily animals (birds and fish) were also used as lamps after being threaded with a wick. Fireflies have been used as lighting sources. Candles and glass and pottery lamps were also invented. Chandeliers were an early form of "light fixture".

The hollow worked stones lamps found in Lascaux caves date back how far?
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A: 15,000 years


Problem: Like the reptiles, birds are primarily uricotelic, that is, their kidneys extract nitrogenous waste from their bloodstream and excrete it as uric acid instead of urea or ammonia through the ureters into the intestine. Birds do not have a urinary bladder or external urethral opening and (with exception of the ostrich) uric acid is excreted along with feces as a semisolid waste. However, birds such as hummingbirds can be facultatively ammonotelic, excreting most of the nitrogenous wastes as ammonia. They also excrete creatine, rather than creatinine like mammals. This material, as well as the output of the intestines, emerges from the bird's cloaca. The cloaca is a multi-purpose opening: waste is expelled through it, most birds mate by joining cloaca, and females lay eggs from it. In addition, many species of birds regurgitate pellets. Males within Palaeognathae (with the exception of the kiwis), the Anseriformes (with the exception of screamers), and in rudimentary forms in Galliformes (but fully developed in Cracidae) possess a penis, which is never present in Neoaves. The length is thought to be related to sperm competition. When not copulating, it is hidden within the proctodeum compartment within the cloaca, just inside the vent. The digestive system of birds is unique, with a crop for storage and a gizzard that contains swallowed stones for grinding food to compensate for the lack of teeth. Most birds are highly adapted for rapid digestion to aid with flight. Some migratory birds have adapted to use protein from many parts of their bodies, including protein from the intestines, as additional energy during migration.
What is a multi-purpose opening on birds?
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Answer: cloaca


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
No Islamic visual images or depictions of God are meant to exist because it is believed that such artistic depictions may lead to idolatry. Moreover, Muslims believe that God is incorporeal, making any two- or three- dimensional depictions impossible. Instead, Muslims describe God by the names and attributes that, according to Islam, he revealed to his creation. All but one sura of the Quran begins with the phrase "In the name of God, the Beneficent, the Merciful". Images of Mohammed are likewise prohibited. Such aniconism and iconoclasm can also be found in Jewish and some Christian theology.
Why is depicting God forbidden in the Islamic world?
A: such artistic depictions may lead to idolatry


Context and question: The brain generally forms a ring round the pharynx (throat), consisting of a pair of ganglia (local control centers) above and in front of the pharynx, linked by nerve cords either side of the pharynx to another pair of ganglia just below and behind it. The brains of polychaetes are generally in the prostomium, while those of clitellates are in the peristomium or sometimes the first segment behind the peristomium. In some very mobile and active polychaetes the brain is enlarged and more complex, with visible hindbrain, midbrain and forebrain sections. The rest of the central nervous system is generally "ladder-like", consisting of a pair of nerve cords that run through the bottom part of the body and have in each segment paired ganglia linked by a transverse connection. From each segmental ganglion a branching system of local nerves runs into the body wall and then encircles the body. However, in most polychaetes the two main nerve cords are fused, and in the tube-dwelling genus Owenia the single nerve chord has no ganglia and is located in the epidermis.
What nerve cords are never fused in polychaetes?
Answer: unanswerable


Question: Tristan is primarily known for its wildlife. The island has been identified as an Important Bird Area by BirdLife International because there are 13 known species of breeding seabirds on the island and two species of resident land birds. The seabirds include northern rockhopper penguins, Atlantic yellow-nosed albatrosses, sooty albatrosses, Atlantic petrels, great-winged petrels, soft-plumaged petrels, broad-billed prions, grey petrels, great shearwaters, sooty shearwaters, Tristan skuas, Antarctic terns and brown noddies. Tristan and Gough Islands are the only known breeding sites in the world for the Atlantic petrel (Pterodroma incerta; IUCN status EN). Inaccessible Island is also the only known breeding ground of the Spectacled Petrel (Procellaria conspicillata; IUCN Vulnerable). The Tristan albatross (IUCN status CR) is known to breed only on Gough and Inaccessible Islands: all nest on Gough except for one or two pairs who nest on Inaccessible Island.
Is there an answer to this question: Where is the only known breeding site of the Tristan Petrel?

Answer: unanswerable


Problem: Marvel Comics:

In late 1994, Marvel acquired the comic book distributor Heroes World Distribution to use as its own exclusive distributor. As the industry's other major publishers made exclusive distribution deals with other companies, the ripple effect resulted in the survival of only one other major distributor in North America, Diamond Comic Distributors Inc. In early 1997, when Marvel's Heroes World endeavor failed, Diamond also forged an exclusive deal with Marvel—giving the company its own section of its comics catalog Previews.

The failure of what high profile business initiative caused Marvel to approach Diamond?
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A:
Marvel's Heroes World