Problem 4. The following data were obtained in some statistical sample which contained 100 elements. Value Count 20 40 3 30 10 The column "Count" shows the number of times the corresponding value appeared in the sample. (a) Compute estimates of the population mean and population standard deviation. (b) Construct 90% and 95% confidence intervals for the population mean. (c) Construct a 80% confidence interval for the population proportion of elements with value 2 or more. 1