Problem: Time:

The most accurate timekeeping devices are atomic clocks, which are accurate to seconds in many millions of years, and are used to calibrate other clocks and timekeeping instruments. Atomic clocks use the frequency of electronic transitions in certain atoms to measure the second. One of the most common atoms used is caesium, most modern atomic clocks probe caesium with microwaves to determine the frequency of these electron vibrations. Since 1967, the International System of Measurements bases its unit of time, the second, on the properties of caesium atoms. SI defines the second as 9,192,631,770 cycles of the radiation that corresponds to the transition between two electron spin energy levels of the ground state of the 133Cs atom.

Which system bases its unit of time on the properties of caesium?
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A: the International System of Measurements

Problem: Napoleon:

Napoleon ended lawlessness and disorder in post-Revolutionary France. He was, however, considered a tyrant and usurper by his opponents. His critics charge that he was not significantly troubled when faced with the prospect of war and death for thousands, turned his search for undisputed rule into a series of conflicts throughout Europe and ignored treaties and conventions alike. His role in the Haitian Revolution and decision to reinstate slavery in France's oversea colonies are controversial and have an impact on his reputation.

Who charge that Napoleon was untroubled by the prospect of war and death for thousands?
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A: His critics

Problem: Pharmaceutical industry:

In April 1994, the results of a Merck-sponsored study, the Scandinavian Simvastatin Survival Study, were announced. Researchers tested simvastatin, later sold by Merck as Zocor, on 4,444 patients with high cholesterol and heart disease. After five years, the study concluded the patients saw a 35% reduction in their cholesterol, and their chances of dying of a heart attack were reduced by 42%. In 1995, Zocor and Mevacor both made Merck over US$1 billion. Endo was awarded the 2006 Japan Prize, and the Lasker-DeBakey Clinical Medical Research Award in 2008. For his "pioneering research into a new class of molecules" for "lowering cholesterol,"[sentence fragment]

What study did Merk sponsor in 1994?
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A: Scandinavian Simvastatin Survival Study

Problem: Frederic Chopin:

Chopin also endowed popular dance forms with a greater range of melody and expression. Chopin's mazurkas, while originating in the traditional Polish dance (the mazurek), differed from the traditional variety in that they were written for the concert hall rather than the dance hall; "it was Chopin who put the mazurka on the European musical map." The series of seven polonaises published in his lifetime (another nine were published posthumously), beginning with the Op. 26 pair (published 1836), set a new standard for music in the form. His waltzes were also written specifically for the salon recital rather than the ballroom and are frequently at rather faster tempos than their dance-floor equivalents.

Chopin's Polish dance music was developed for what type of hall?
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A:
concert hall