Which measure of variability is the most appropriate for this set of values?
13, 42, 104, 36, 28, 6, 17

Three of the most knowns measure of variability are variance, standard deviation, and interquartile range. Because the given set of values are very far from each other and are also very much scattered, the best measure of variability is the VARIANCE. 

Ifound this on google “a skewed (non-symmetric) distribution is a distribution in which there is no such mirror-imaging. a "skewed right" distribution is one in which the tail is on the right side. a "skewed left" distribution is one in which the tail is on the left side. the above histogram is for a distribution that is skewed right.” i hope this you for what your looking for