The number of credits being taken by a sample of 13​ full-time college students are listed below. find the​ mean, median, and mode of the​ data, if possible. if any measure cannot be found or does not represent the center of the​ data, explain why. 8    8    11    11    8    9    7    7    7    7    7    7    10    find the mean. select the correct choice below​ and, if​ necessary, fill in the answer box to complete your choice.
a. the mean is nothing . ​(type an integer or decimal rounded to one decimal place as​ needed.)
b. the data set does not have a mean.