A randon sample of monthly gasoline bills for a company's 15 sales persons are:$216-254-247-257-231-265-221-226-228-252-235-265-272-285-266. what is the mean? what is the median? what is the value of quartile 3? what is the value of the mode? the range is equal to? what is the value of the standard deviation? what is the value of the coefficient of variation? do not express the answer as a percent, leave it as a ratio, eg .123are the numbers skewed positively, negatively or are they symmetrical? (for your answer enter only one word: positively, negatively or symmetrical. what is the value of the coefficient of skewness using pearson's coefficient of skewness? what is the value of quartile 2?