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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

4. suppose that pollution in a neighborhood comes from two factories, with marginal benefit curves given by mb1 = 12 – p1 and mb2 = 8 – p2. the level of pollution in the neighborhood is given by p = p1 + p2. the government wants to limit pollution by instituting a pollution-rights market. the government’s desired level of p is 10, so it prints 10 pollution rights and offers them for sale to the firms. a)find the equilibrium selling price of a pollution right, as well as the allocation of rights (and hence pollution levels) across the two factories. b)repeat part (a) for the case where the government’s desired level of pollution equals 14. c)comment on the usefulness of a pollution rights market in achieving efficient levels of pollution abatement.

Which of the following is not part of the mission statement of the department of homeland security? lead the unified national effort to secure america protect against and respond to threats and hazards to the nation ensure safe and secure borders coordinate intelligence operations against terrorists in other countries