Experian Marketing Services reported that the typical American spends 144 minutes (2.4 hours) per day accessing the Internet through a mobile device. (Source: The 2014 Digital Marketer, available at...

Experian Marketing Services reported that the typical American spends 144 minutes (2.4 hours) per day accessing the Internet through a mobile device. (Source: The 2014 Digital Marketer, available at ex.pn/1kXJjfX.) You wonder if males and females spend differing amounts of time per day accessing the Internet through a mobile device.

You select a sample of 60 friends and family (30 males and 30 females), collect times spent per day accessing the Internet through a mobile device (in minutes), and store the data collected in internetMobileTime2.

a. Using a 0.05 level of significance, is there evidence of a difference in the variances of time spent per day accessing the Internet via mobile device between males and females?

b. On the basis of the results in (a), which t test defined in Section 10.1 should you use to compare the means of males and females? Discuss.