2. A random sample of voters in Nashville, Tennessee, is classified by age group, as shown by the following data. a. Calculate the mean of the data. b. Calculate the mode. c. Calculate the median. d. Calculate the variance. e. Calculate the standard deviation f. Calculate the range and the coefficient of range. \begin{tabular}{[111]] \hline Age Group & Frequency (f) W \hline $30-40$ & 4 Thline $40-50$ & 6 W \hline $50-60$ & 8 Thline $60-70$ & 12 \hline $70-80$ & 9W \hline $80-90$ & 7 \hline $90-100$ & 4 W \hline \end{tabular SP.PC. 120