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Bitumen was used in early photographic technology. In 1826 or 1827, it was used by French scientist Joseph Nicéphore Niépce 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 did exposure to light harden and make soluble?
A: unanswerable

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The waterwheel appeared in Chinese records during the Han. As mentioned by Huan Tan in about 20 AD, they were used to turn gears that lifted iron trip hammers, and were used in pounding, threshing and polishing grain. However, there is no sufficient evidence for the watermill in China until about the 5th century. The Nanyang Commandery Administrator Du Shi (d. 38 AD) created a waterwheel-powered reciprocator that worked the bellows for the smelting of iron. Waterwheels were also used to power chain pumps that lifted water to raised irrigation ditches. The chain pump was first mentioned in China by the philosopher Wang Chong in his 1st-century-AD Balanced Discourse.
During what century is it likely that the watermill made an appearance in China?
A: about the 5th century

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With 120,000 students in London, the federal University of London is the largest contact teaching university in the UK. It includes four large multi-faculty universities – King's College London, Queen Mary, Royal Holloway and UCL – and a number of smaller and more specialised institutions including Birkbeck, the Courtauld Institute of Art, Goldsmiths, Guildhall School of Music and Drama, the Institute of Education, the London Business School, the London School of Economics, the London School of Hygiene & Tropical Medicine, the Royal Academy of Music, the Central School of Speech and Drama, the Royal Veterinary College and the School of Oriental and African Studies. Members of the University of London have their own admissions procedures, and some award their own degrees.
From what school in London would a student receive an MBA?
A: the London Business School

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Davies' and Gribbin's objections are shared by proponents of digital physics who view information rather than matter to be fundamental. Their objections were also shared by some founders of quantum theory, such as Max Planck, who wrote:
Who founded digital physics? 
A:
unanswerable