Question 8 of 8 de The standard deviation of a variable is 17. If a sample of 85 individuals is selected, (a) Find the standard error of the mean. (b) Find the sample size needed to cut the standard error of the mean in half. Part 1 of 2 (a) Find the standard error of the mean. Round the answer to three decimal places. Standard error of the mean = Part 2 of 2 (b) Find the sample size needed to cut the standard error of the mean in half. Round intermediate calculations to three decimal places and round your final answer up to the nearest whole number. Sample size =