Q6. Of 1000 randomly selected cases of lung cancer, 823 resulted in death within 10 years.
(a) Calculate a 95% two-sided confidence interval on the death rate from lung cancer.
(b) Using the point estimate of p obtained from the preliminary sample, what sample size is needed to be 95% confident that the error in estimating the true value of p is less than 0.03?
(c) How large must the sample be if you wish to be at least 95% confident that the error in estimating p is less than 0.03, regardless of the true value of p?