In a survey of 12 owners of a certain model of car, the following values for average fuel consumption were reported: 25.5, 31.1, 29.6, 32.4, 39.4, 28.9, 33.3, 31.4, 29.5, 30.5, 31.7, 29.2 Calculate the mean value, the standard deviation, and the standard error of the mean for the reported consumption values. Express the mean consumption value and possible error in the mean expressed to a 95.4% confidence level