A physical therapist is investigating the mean recovery time after ACL surgery for patients involved in a new therapy regimen. For the purpose of the study, a successful recovery was defined to be the ability to walk without crutches. For 38 randomly selected patients, the mean recovery time after ACL surgery was found to be 22.6 days. Assume that the population standard deviation is 3.7 days. Find a 99% confidence interval for the mean recovery time for all ACL surgery patients undergoing the same new therapy. Round all answers toone decimal place.