Problem: To make pulp from wood, a chemical pulping process separates lignin from cellulose fibres. This is accomplished by dissolving lignin in a cooking liquor, so that it may be washed from the cellulose; this preserves the length of the cellulose fibres. Paper made from chemical pulps are also known as wood-free papersnot to be confused with tree-free paper; this is because they do not contain lignin, which deteriorates over time. The pulp can also be bleached to produce white paper, but this consumes 5% of the fibres; chemical pulping processes are not used to make paper made from cotton, which is already 90% cellulose.
What percentage of cotton is not cellulose?
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Answer: unanswerable

Problem: The first written account of a game played was on October 15, 1862, on the Montreal Cricket Grounds. It was between the First Battalion Grenadier Guards and the Second Battalion Scots Fusilier Guards resulting in a win by the Grenadier Guards 3 goals, 2 rouges to nothing.[citation needed] In 1864, at Trinity College, Toronto, F. Barlow Cumberland, Frederick A. Bethune, and Christopher Gwynn, one of the founders of Milton, Massachusetts, devised rules based on rugby football. The game gradually gained a following, with the Hamilton Football Club formed on November 3, 1869, (the oldest football club in Canada). Montreal formed a team April 8, 1872, Toronto was formed on October 4, 1873, and the Ottawa FBC on September 20, 1876.
What team was formed on April 8, 1827?
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Answer: unanswerable

Problem: Brass, which is an alloy of copper and zinc, has been used since at least the 10th century BC in Judea and by the 7th century BC in Ancient Greece. Zinc metal was not produced on a large scale until the 12th century in India and was unknown to Europe until the end of the 16th century. The mines of Rajasthan have given definite evidence of zinc production going back to the 6th century BC. To date, the oldest evidence of pure zinc comes from Zawar, in Rajasthan, as early as the 9th century AD when a distillation process was employed to make pure zinc. Alchemists burned zinc in air to form what they called "philosopher's wool" or "white snow".
What early process was used to dissolve zinc?
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Answer:
unanswerable