A simple random sample of 20 items resulted in a sample mean of 20. The population standard deviation is a = 6. Round your answers to two decimal places. a. What is the standard error of the mean, ? O b. At 95% confidence, what is the margin of error? X 1.90 3.72

A simple random sample of 20 items resulted in a sample mean of 20 . The population standard deviation is =6. Round your answers to two decimal places. a. What is the standard error of the mean, Y ? b. At 95% confidence, what is the margin of error