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The hawthorne works was a large western electric factory with 45,000 employees. during the 1920s and 1930s, hawthorne works was the site of some well-known industrial studies. in one of the studies, researchers investigated the impact of different working conditions on worker productivity. prior to the start of the study, researchers secretly measured workers' productivity for several weeks. then researchers chose two workers, who then chose their own teams. the teams were separated from the general workforce and completed their work in different experiment rooms where the researchers could observe them more easily. over a 5-year period researchers manipulated the structure of the workday for each team (number and duration of breaks and number of hours per shift). for each of these changes in working conditions, the researchers measured the effect on productivity. for some conditions, such as frequent short breaks, workers rebelled by intentionally decreasing productivity.why did the researchers secretly measure the workers' productivity before creating the two treatment groups? a, to create similar treatment groups so that a cause-and-effect relationship could be establishedb, to draw conclusions about the productivity of all workers in the plant based on the test groupsc, to directly control for confounding variablesd, to provide a baseline for measuring worker productivity

On december 31, 2013, coronado company issues 173,000 stock-appreciation rights to its officers entitling them to receive cash for the difference between the market price of its stock and a pre-established price of $10. the fair value of the sars is estimated to be $5 per sar on december 31, 2014; $2 on december 31, 2015; $10 on december 31, 2016; and $8 on december 31, 2017. the service period is 4 years, and the exercise period is 7 years. prepare a schedule that shows the amount of compensation expense allocable to each year affected by the stock-appreciation rights plan.

Problem page a medical equipment industry manufactures x-ray machines. the unit cost c (the cost in dollars to make each x-ray machine) depends on the number of machines made. if x machines are made, then the unit cost is given by the function =cx+−0.3x2126x31,935 . how many machines must be made to minimize the unit cost?