Problem: Asphalt:

Bitumen was used in early photographic technology. In 1826 or 1827, it was used by French scientist Joseph Nicephore Niepce to make the oldest surviving photograph from nature. The bitumen was thinly coated onto a pewter plate which was then exposed in a camera. Exposure to light hardened the bitumen and made it insoluble, so that when it was subsequently rinsed with a solvent only the sufficiently light-struck areas remained. Many hours of exposure in the camera were required, making bitumen impractical for ordinary photography, but from the 1850s to the 1920s it was in common use as a photoresist in the production of printing plates for various photomechanical printing processes.[not in citation given]

What feature of bitumen use in photography made it impractical?
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A: hours of exposure

Problem: The City of Charleston is served by the Charleston International Airport. It is located in the City of North Charleston and is about 12 miles (20 km) northwest of downtown Charleston. It is the busiest passenger airport in South Carolina (IATA: CHS, ICAO: KCHS). The airport shares runways with the adjacent Charleston Air Force Base. Charleston Executive Airport is a smaller airport located in the John's Island section of the city of Charleston and is used by noncommercial aircraft. Both airports are owned and operated by the Charleston County Aviation Authority.
What military base is located nowhere near the airport?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
London's buildings are too diverse to be characterised by any particular architectural style, partly because of their varying ages. Many grand houses and public buildings, such as the National Gallery, are constructed from Portland stone. Some areas of the city, particularly those just west of the centre, are characterised by white stucco or whitewashed buildings. Few structures in central London pre-date the Great Fire of 1666, these being a few trace Roman remains, the Tower of London and a few scattered Tudor survivors in the City. Further out is, for example, the Tudor period Hampton Court Palace, England's oldest surviving Tudor palace, built by Cardinal Thomas Wolsey c.1515.
What is England's oldest standing palace from the Tudor period?
A: Hampton Court Palace

Context and question: The Indian Institute of Technology Mandi, Himachal Pradesh University Shimla, Institute of Himalayan Bioresource Technology (IHBT, CSIR Lab), Palampur, the National Institute of Technology, Hamirpur, Indian Institute of Information Technology, Una the Central University Dharamshala, AP Goyal (Alakh Prakash Goyal) Shimla University, The Bahra University (Waknaghat, Solan) the Baddi University of Emerging Sciences and Technologies Baddi, IEC University, Shoolini University Of Biotechnology and Management Sciences, Solan, Manav Bharti University Solan, the Jaypee University of Information Technology Waknaghat, Eternal University, Sirmaur & Chitkara University Solan are some of the pioneer universities in the state. CSK Himachal Pradesh Krishi Vishwavidyalya Palampur is one of the most renowned hill agriculture institutes in world. Dr. Yashwant Singh Parmar University of Horticulture and Forestry has earned a unique distinction in India for imparting teaching, research and extension education in horticulture, forestry and allied disciplines. Further, state-run Jawaharlal Nehru Government Engineering College started in 2006 at Sundernagar.
When was the state run Nehru Government Engineering College started?
Answer: 2006 at Sundernagar

Question: Geologically, West Antarctica closely resembles the Andes mountain range of South America. The Antarctic Peninsula was formed by uplift and metamorphism of sea bed sediments during the late Paleozoic and the early Mesozoic eras. This sediment uplift was accompanied by igneous intrusions and volcanism. The most common rocks in West Antarctica are andesite and rhyolite volcanics formed during the Jurassic period. There is also evidence of volcanic activity, even after the ice sheet had formed, in Marie Byrd Land and Alexander Island. The only anomalous area of West Antarctica is the Ellsworth Mountains region, where the stratigraphy is more similar to East Antarctica.
Is there an answer to this question: What type of geologic activity occurred even after the formation of the ice sheets?

Answer: volcanic

Question: Greece is a developed country with an economy based on the service (82.8%) and industrial sectors (13.3%). The agricultural sector contributed 3.9% of national economic output in 2015. Important Greek industries include tourism and shipping. With 18 million international tourists in 2013, Greece was the 7th most visited country in the European Union and 16th in the world. The Greek Merchant Navy is the largest in the world, with Greek-owned vessels accounting for 15% of global deadweight tonnage as of 2013. The increased demand for international maritime transportation between Greece and Asia has resulted in unprecedented investment in the shipping industry.
Is there an answer to this question: How many international tourists were imprisoned in Greece in 2013?

Answer:
unanswerable