Problem: Paper:

Paper made from wood pulp is not necessarily less durable than a rag paper. The ageing behavior of a paper is determined by its manufacture, not the original source of the fibres. Furthermore, tests sponsored by the Library of Congress prove that all paper is at risk of acid decay, because cellulose itself produces formic, acetic, lactic and oxalic acids.

What does oxalic acid produce?
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A: unanswerable

Problem: Capital punishment in the United States:

Previous post-Furman mass clemencies took place in 1986 in New Mexico, when Governor Toney Anaya commuted all death sentences because of his personal opposition to the death penalty. In 1991, outgoing Ohio Governor Dick Celeste commuted the sentences of eight prisoners, among them all four women on the state's death row. And during his two terms (19791987) as Florida's Governor, Bob Graham, although a strong death penalty supporter who had overseen the first post-Furman involuntary execution as well as 15 others, agreed to commute the sentences of six people on the grounds of "possible innocence" or "disproportionality."

How many women were on Ohio's death row in 1991?
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A: four

Problem: Mexico City:

The most recognizable icon of Mexico City is the golden Angel of Independence on the wide, elegant avenue Paseo de la Reforma, modeled by the order of the Emperor Maximilian of Mexico after the Champs-Elysees in Paris. This avenue was designed over the Americas' oldest known major roadway in the 19th century to connect the National Palace (seat of government) with the Castle of Chapultepec, the imperial residence. Today, this avenue is an important financial district in which the Mexican Stock Exchange and several corporate headquarters are located. Another important avenue is the Avenida de los Insurgentes, which extends 28.8 km (17.9 mi) and is one of the longest single avenues in the world.

Who made the Angel of Independence?
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A: the order of the Emperor Maximilian

Problem: Time:

Psychoactive drugs can impair the judgment of time. Stimulants can lead both humans and rats to overestimate time intervals, while depressants can have the opposite effect. The level of activity in the brain of neurotransmitters such as dopamine and norepinephrine may be the reason for this. Such chemicals will either excite or inhibit the firing of neurons in the brain, with a greater firing rate allowing the brain to register the occurrence of more events within a given interval (speed up time) and a decreased firing rate reducing the brain's capacity to distinguish events occurring within a given interval (slow down time).

What do rats not understand?
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A:
unanswerable