Researchers have begun to hypothesize that pesticide exposure is linked to risk of developing pancreatic cancer. In order to collect preliminary data on a potential association, investigators decide to look at rates of pesticide exposure among 60 countries and rates of pancreatic cancer. Pesticide exposure was categorized as high, moderate, and low. Their results showed a strong correlation between high pesticide exposure and the development of pancreatic cancer. The investigators concluded that more research would need to be done before definitively linking pesticide exposure to the risk of pancreatic cancer. Pancreatic cancer is a rare disease.

On what basis did you determine which type of study this represents? Include all of the following: initial classification of study subjects; prospective, retrospective, or concurrent; unit of observation; and the number of observations (i. e. the number of data collection points by the investigator).

marginal cost is a microeconomic measure that us to evaluate the extent to which the level of production of a good is sustainable in accounting, that is, to how many quantities the company plans to profit from the production of the good.

the concept of marginal cost is simple, it means the cost of producing one more item. for example, in the case of pies, the marginal cost is the cost of producing one more pie than those that have already been produced.

it is important to understand that productive activity influences marginal cost. the marginal cost of some goods can be very high, while others may be insignificant. for example, the marginal cost of producing an extra plane is very high. already the marginal cost of a water company to provide 1l more water is derisory.

in the case of pies, the cost involves the inputs, the labor and the fixed cost, which involves the fixed space of the bakery. the level of production initially has the marginal cost decreasing because there is space and manpower available. however, to produce more you have to hire more workers and buy more inputs. if physical space is limited, workers will conflict with places, inputs and their productivity will decrease, meaning there is an optimum point of production for each level of space and manpower. from this point on, the productivity of the workers will be getting smaller because of lack of space, so that the marginal cost of producing one more pie will be increasing. so, although you have not posted the chart, but if you have the answer, you can see that my explanation goes according to the marginal cost curve that will increase from the 4th pie, answer (c).

answer; criterion validity

answer; collectivism;