QUES: 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 papers–not 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 is combined with lignin when making pulp?
What is the answer?
ANS: unanswerable
QUES: Long a major population center and site of worldwide automobile manufacturing, Detroit has suffered a long economic decline produced by numerous factors. Like many industrial American cities, Detroit reached its population peak in the 1950 census. The peak population was 1.8 million people. Following suburbanization, industrial restructuring, and loss of jobs (as described above), by the 2010 census, the city had less than 40 percent of that number, with just over 700,000 residents. The city has declined in population in each census since 1950.

What was the population of Detroit in 1950?
What is the answer?
ANS: 1.8 million
QUES: While pursuing his PhD at Princeton, Feynman married his high school sweetheart, Arline Greenbaum (often misspelled "Arlene"), despite the knowledge that she was seriously ill with tuberculosis—an incurable disease at the time. She died in 1945. In 1946, Feynman wrote a letter to her, expressing his deep love and heartbreak, that he kept for the rest of his life. ("Please excuse my not mailing this," the letter concluded, "but I don't know your new address.") This portion of Feynman's life was portrayed in the 1996 film Infinity, which featured Feynman's daughter, Michelle, in a cameo role.

Who played a cameo in a film about Feynman?
What is the answer?
ANS:
Feynman's daughter, Michelle