The following data are the lengths of 16 ears (cm) collected in a study of size inheritance in a hybrid variety of corn: 18,15,14,11,18,19,16,16,17,12,15,16 ,12,15,13,17. the sample mean is 15.25 and the sample standard deviation is 2.35. assume the length of ears in the population is normally distributed. construct the lower bound for a 95% confidence interval for the mean length of ears in plants of this variety. give your answer to 3 decimal places.