Problem: Hydrostatic gauges (such as the mercury column manometer) consist of a vertical column of liquid in a tube whose ends are exposed to different pressures. The column will rise or fall until its weight is in equilibrium with the pressure differential between the two ends of the tube. The simplest design is a closed-end U-shaped tube, one side of which is connected to the region of interest. Any fluid can be used, but mercury is preferred for its high density and low vapour pressure. Simple hydrostatic gauges can measure pressures ranging from 1 torr (100 Pa) to above atmospheric. An important variation is the McLeod gauge which isolates a known volume of vacuum and compresses it to multiply the height variation of the liquid column. The McLeod gauge can measure vacuums as high as 106 torr (0.1 mPa), which is the lowest direct measurement of pressure that is possible with current technology. Other vacuum gauges can measure lower pressures, but only indirectly by measurement of other pressure-controlled properties. These indirect measurements must be calibrated via a direct measurement, most commonly a McLeod gauge.
What is the lowest amount of mercury that can be measured in the air?
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Answer: unanswerable

Problem: In the judgment of political scientist Randall Ripley, since 1883 "the candidate for Speaker nominated by the minority party has clearly been the Minority Leader." However, this assertion is subject to dispute. On December 3, 1883, the House elected Democrat John G. Carlisle of Kentucky as Speaker. Republicans placed in nomination for the speakership J. Warren Keifer of Ohio, who was Speaker the previous Congress. Clearly, Keifer was not the Republicans' minority leader. He was a discredited leader in part because as Speaker he arbitrarily handed out "choice jobs to close relatives ... all at handsome salaries." Keifer received "the empty honor of the minority nomination. But with it came a sting -- for while this naturally involves the floor leadership, he was deserted by his [partisan] associates and his career as a national figure terminated ingloriously." Representative Thomas Reed, R-ME, who later became Speaker, assumed the de facto role of minority floor leader in Keifer's stead. "[A]lthough Keifer was the minority's candidate for Speaker, Reed became its acknowledged leader, and ever after, so long as he served in the House, remained the most conspicuous member of his party.
Why was Keifer discredited/empty leader?
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Answer: arbitrarily handed out "choice jobs to close relatives ... all at handsome salaries.

Problem: The alcohol in beer comes primarily from the metabolism of sugars that are produced during fermentation. The quantity of fermentable sugars in the wort and the variety of yeast used to ferment the wort are the primary factors that determine the amount of alcohol in the final beer. Additional fermentable sugars are sometimes added to increase alcohol content, and enzymes are often added to the wort for certain styles of beer (primarily "light" beers) to convert more complex carbohydrates (starches) to fermentable sugars. Alcohol is a by-product of yeast metabolism and is toxic to the yeast; typical brewing yeast cannot survive at alcohol concentrations above 12% by volume. Low temperatures and too little fermentation time decreases the effectiveness of yeasts and consequently decreases the alcohol content.
Where do the sugars in beer come from?
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Answer:
unanswerable