According to a study of political prisoners, the mean duration of imprisonment for 30 prisoners with chronic post traumatic stress disorder (PTSD) was 33.2 months. Assuming that =40 months, determine a 90% confidence interval for the mean duration of imprisonment, , of all political prisoners with chronic PTSD. Interpret your answer in words.

A. 90% confidence interval for the population mean is from = months to = months.

B.I nterpret the confidence interval. Select the correct choice below and fill in the answer boxes to complete your choice.

a.We can be 90% confident that the mean duration of imprisonment, , of all political prisoners with chronic PTSD is somewhere between months = and months.

b.There is a 90% chance the mean duration of imprisonment, , of all political prisoners with chronic PTSD will equal the mean of the interval from months to months.