average mileage in miles per gallon (mpg) of 15 different brands of snowmobiles with a 2000 cc engine is listed below: 14 15 12 11 16 14 15 13 12 11 13 17 12 15 14 c. Indicate whether the data shows any kind of skewness. If so, comment on the distribution. b. Calculate the variance, standard deviation, range, coefficient of variation, and Z score. If the values indicated above are increased by 3 mpg due to an enhanced design of a newly introduced fuel injection system, calculate all the requested values in parts (a) through (c). a. Calculate the mean, median, and mode.