Problem: Sumer:

This period is generally taken to coincide with a major shift in population from southern Mesopotamia toward the north. Ecologically, the agricultural productivity of the Sumerian lands was being compromised as a result of rising salinity. Soil salinity in this region had been long recognized as a major problem. Poorly drained irrigated soils, in an arid climate with high levels of evaporation, led to the buildup of dissolved salts in the soil, eventually reducing agricultural yields severely. During the Akkadian and Ur III phases, there was a shift from the cultivation of wheat to the more salt-tolerant barley, but this was insufficient, and during the period from 2100 BC to 1700 BC, it is estimated that the population in this area declined by nearly three fifths. This greatly upset the balance of power within the region, weakening the areas where Sumerian was spoken, and comparatively strengthening those where Akkadian was the major language. Henceforth Sumerian would remain only a literary and liturgical language, similar to the position occupied by Latin in medieval Europe.

How much did the population of the region decline due to the decrease in crop productivity?
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A: by nearly three fifths

Problem: Modern history:

The creation of a modern industrial economy took place. With the creation of a transportation and communication infrastructure, the corporation became the dominant form of business organization and a managerial revolution transformed business operations. In 1890, Congress passed the Sherman Antitrust Actthe source of all American anti-monopoly laws. The law forbade every contract, scheme, deal, or conspiracy to restrain trade, though the phrase "restraint of trade" remained subjective. By the beginning of the 20th century, per capita income and industrial production in the United States exceeded that of any other country except Britain. Long hours and hazardous working conditions led many workers to attempt to form labor unions despite strong opposition from industrialists and the courts. But the courts did protect the marketplace, declaring the Standard Oil group to be an "unreasonable" monopoly under the Sherman Antitrust Act in 1911. It ordered Standard to break up into 34 independent companies with different boards of directors.

What transformed business organization in 1890?
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A: managerial revolution

Problem: Database:

Just as the navigational approach would require programs to loop in order to collect records, the relational approach would require loops to collect information about any one record. Codd's solution to the necessary looping was a set-oriented language, a suggestion that would later spawn the ubiquitous SQL. Using a branch of mathematics known as tuple calculus, he demonstrated that such a system could support all the operations of normal databases (inserting, updating etc.) as well as providing a simple system for finding and returning sets of data in a single operation.

How does a program collect information using a navigational system?
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A: require programs to loop

Problem: Energy:

Energy transfer can be considered for the special case of systems which are closed to transfers of matter. The portion of the energy which is transferred by conservative forces over a distance is measured as the work the source system does on the receiving system. The portion of the energy which does not do work during the transfer is called heat.[note 4] Energy can be transferred between systems in a variety of ways. Examples include the transmission of electromagnetic energy via photons, physical collisions which transfer kinetic energy,[note 5] and the conductive transfer of thermal energy.

The portion of energy which works during the transfer is called what?
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A:
unanswerable