In a survey to determine the amount of crop yield due to an air pollutant, a simple random sample of n = 20 plots was selected from N = 1000 in the population. The summary statistics on yield yi (in weight) and level of pol
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a) Estimate the mean yield for the population with a linear regression estimate.
(b) Estimate the variance of the linear regression estimate.
(c) Predict the yield on a plot in which the pollutant level is xi = 4.