The proportion of deaths due to lung cancer in males ages 15-64 in England and Wales during the period 1970-1972(2 years) was 12%(0.12). Suppose that of 20 deaths that occur among male workers in this age group who have worked for at least 1 year in a chemical plant, 5 are due to lung cancer. We wish to determine whether there is a difference between the proportion of deaths from lung cancer in this plant and the proportion in the general population.

A.Construct the appropriate 95% confidence interval for the proportion of deaths from lung cancer in the sample.

B.What is the power of your test assessing the proportion of lung cancer deaths? (inspired by problems 7.35-7.37 in Rosner)