You are interested in the flowering time of tulips in early spring and decided to keep track of the date that different gardens in your neighborhood bloom. You use April 1st as a reference point and record the number of days past this date for each garden. You sample 12 gardens and find that the average number of days is 12.7 with a standard deviation of 3.1. What is the 95% confidence interval for the average days past April 1st that the gardens bloomed based on this sample?