The following sample data are from a normal population: 10, 8, 12, 15, 13, 11, 6, 5.
a. What is the point estimate of the population standard deviation (to 2 decimals)?
b. With 95% confidence, what is the margin of error for the estimation of the population mean (to 1 decimal)?
c. What is the 95% confidence interval for the population mean (to 1 decimal)?