Problem: Zinc:

Although not yet tested as a therapy in humans, a growing body of evidence indicates that zinc may preferentially kill prostate cancer cells. Because zinc naturally homes to the prostate and because the prostate is accessible with relatively non-invasive procedures, its potential as a chemotherapeutic agent in this type of cancer has shown promise. However, other studies have demonstrated that chronic use of zinc supplements in excess of the recommended dosage may actually increase the chance of developing prostate cancer, also likely due to the natural buildup of this heavy metal in the prostate.

What could normal use of zinc possibly cause?
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A: unanswerable

Problem: United States dollar:

The decline in the value of the U.S. dollar corresponds to price inflation, which is a rise in the general level of prices of goods and services in an economy over a period of time. A consumer price index (CPI) is a measure estimating the average price of consumer goods and services purchased by households. The United States Consumer Price Index, published by the Bureau of Labor Statistics, is a measure estimating the average price of consumer goods and services in the United States. It reflects inflation as experienced by consumers in their day-to-day living expenses. A graph showing the U.S. CPI relative to 19821984 and the annual year-over-year change in CPI is shown at right.

What does the decline in value of the average price correspond to?
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A: unanswerable

Problem: Modern history:

Europe spent these years rebuilding and coming to terms with the vast human cost of the conflict. The economy of the United States became increasingly intertwined with that of Europe. In Germany, the Weimar Republic gave way to episodes of political and economic turmoil, which culminated with the German hyperinflation of 1923 and the failed Beer Hall Putsch of that same year. When Germany could no longer afford war payments, Wall Street invested heavily in European debts to keep the European economy afloat as a large consumer market for American mass-produced goods. By the middle of the decade, economic development soared in Europe, and the Roaring Twenties broke out in Germany, Britain and France, the second half of the decade becoming known as the "Golden Twenties". In France and francophone Canada, they were also called the "annees folles" ("Crazy Years").

Who invested in European debts?
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A: Wall Street

Problem: Mandolin:

The second decline was not as complete as the first. Thousands of people had learned to play the instrument. Even as the second wave of mandolin popularity declined in the early 20th century, new versions of the mandolin began to be used in new forms of music. Luthiers created the resonator mandolin, the flatback mandolin, the carved-top or arched-top mandolin, the mandolin-banjo and the electric mandolin. Musicians began playing it in Celtic, Bluegrass, Jazz and Rock-n-Roll styles and Classical too.

When did the first wave of mandolin popularity decline?
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A:
unanswerable