what is the probability of the average of the population being less than 11.8 with 97% confidence?

Sample
1	11.4
2	12.1
3	11.9
4	11.4
5	12.1
6	10.9
7	11.8
8	10.7
9	12.4
10	11.5
11	10.3
12	12.2
13	11.7
14	11.5