In the Statistics Norway on-line article "The Times They Are a Changing," J. Kristiansen discussed the changes in age at the time of marriage in Norway. The ages, in years, at the time of marriage for 75 Norwegian couples is presented on the WeissStats site. Use the technology of your choice to do the following.

a. Apply the paired Wilcoxon signed-rank test to decide, at the 1% significance level, whether the data provide sufficient evidence to conclude that the mean age of Norwegian men at the time of marriage exceeds that of Norwegian women.

b. Compare your result in part (a) to the one obtained in Exercise 10.171 on pages 497-498, where the paired t-test was used.

c. Which test do you think is preferable: the paired t-test or the paired Wilcoxon signed-rank test? Explain your answer.