Question: A 1976 study of smokers over 30 years of age who delivered premature babies (fewer than 260 days of gestation) reported an infant survival rate of 72%. Suppose researchers would like to estimate the current survival rate. Based on the assumption that the survival rate today would be roughly similar to the survival rate in 1976, compute the sample size required to estimate the true survival proportion to within .05 with 95% confidence, showing work.