Problem: Roman Republic:

Tiberius Gracchus was elected tribune in 133 BC. He attempted to enact a law which would have limited the amount of land that any individual could own. The aristocrats, who stood to lose an enormous amount of money, were bitterly opposed to this proposal. Tiberius submitted this law to the Plebeian Council, but the law was vetoed by a tribune named Marcus Octavius. Tiberius then used the Plebeian Council to impeach Octavius. The theory, that a representative of the people ceases to be one when he acts against the wishes of the people, was counter to Roman constitutional theory. If carried to its logical end, this theory would remove all constitutional restraints on the popular will, and put the state under the absolute control of a temporary popular majority. His law was enacted, but Tiberius was murdered with 300 of his associates when he stood for reelection to the tribunate.

When was Tiberius Gracchus murdered?
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A: when he stood for reelection to the tribunate

Problem: Cotton:

The era of manufactured fibers began with the development of rayon in France in the 1890s. Rayon is derived from a natural cellulose and cannot be considered synthetic, but requires extensive processing in a manufacturing process, and led the less expensive replacement of more naturally derived materials. A succession of new synthetic fibers were introduced by the chemicals industry in the following decades. Acetate in fiber form was developed in 1924. Nylon, the first fiber synthesized entirely from petrochemicals, was introduced as a sewing thread by DuPont in 1936, followed by DuPont's acrylic in 1944. Some garments were created from fabrics based on these fibers, such as women's hosiery from nylon, but it was not until the introduction of polyester into the fiber marketplace in the early 1950s that the market for cotton came under threat. The rapid uptake of polyester garments in the 1960s caused economic hardship in cotton-exporting economies, especially in Central American countries, such as Nicaragua, where cotton production had boomed tenfold between 1950 and 1965 with the advent of cheap chemical pesticides. Cotton production recovered in the 1970s, but crashed to pre-1960 levels in the early 1990s.

What company produced polyester and nylon in the 1930s and 1940s?
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A: unanswerable

Problem: Mammal:

The oldest known fossil among the Eutheria ("true beasts") is the small shrewlike Juramaia sinensis, or "Jurassic mother from China", dated to 160 million years ago in the Late Jurassic. A later eutherian, Eomaia, dated to 125 million years ago in the Early Cretaceous, possessed some features in common with the marsupials but not with the placentals, evidence that these features were present in the last common ancestor of the two groups but were later lost in the placental lineage. In particular:

What is the oldest know fossil among the Eutheria group?
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A: shrewlike Juramaia sinensis

Problem: Nigeria:

During the oil boom of the 1970s, Nigeria joined OPEC and the huge revenue generated made the economy richer. Despite huge revenues from oil production and sale, the military administration did little to improve the standard of living of the population, help small and medium businesses, or invest in infrastructure. As oil revenues fuelled the rise of federal subventions to states, the federal government became the centre of political struggle and the threshold of power in the country. As oil production and revenue rose, the Nigerian government became increasingly dependent on oil revenues and the international commodity markets for budgetary and economic concerns. It did not develop other sources of the economy for economic stability. That spelled doom to federalism in Nigeria.

Who failed to use the oil revenues to invest in infrastructure?
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A:
the military administration