This question considers the "Brisbane Hospital Records" data from the week 3 work- shop. We are interested in investigating age at death of people who died in Brisbane hospitals in the year 1900. A histogram of the age at death of the 217 patients in the data who died in 1900 is shown below. Brisbane hospital deaths in 1900 by age 20 - 10- 0- 25 50 Age 75 (a) The mean age at death in 1900 was 42.498 with a variance of 332.279. Find a 95% confidence interval for the true mean age at death. (b) Only 46 of the patients lived to age 60 or beyond. Find a 95% confidence interval for the true proportion of patients that live to age 60 or beyond. Please calculate this interval using the "normal approximation" interval. (c) What would the sample size have to increase to in order to narrow the confidence interval found in (b) to just 5 percentage points? You may assume that the observed proportion remains unchanged. count