A hospital would like to determine the mean length of stay for its patients having abdortinal surgery. A sample of 22 patients revealed a sample mean of 5.7 drys and a sample standard deviation of 1.6 days. Assume that the lengths of stay are approximately normally distributed. Find a 95 of confidence interval for the meat iergth of stay for patients with abdominal surgery. found the endpoints to two decimal places, if necessary. Answer Lower Endpainte Upper Endpoint =