You may need to use the appropriate appendix table or technology to answer this question. A simple random sample with n 57 provided a sample mean of 28.5 and a sample standard deviation of 4.4. (Round your answers to one decimal place.) (a) Develop a 90% confidence interval for the population mean. X to (b) Develop a 95% confidence interval for the population mean. x to (c) Develop a 99% confidence interval for the population mean. to (d) What happens to the margin of error and the confidence interval as the confidence level is increased? As the confidence level increases, there is a smaller margin of error and a more narrow confidence interval. As the confidence level increases, there is a larger margin of error and a more narrow confidence interval. O As the confidence level increases, there is a smaller margin of error and a wider confidence interval. As the confidence level increases, there is a larger margin of error and a wider confidence interval. x