An important feature of tablets is battery life, the number of hours before the battery needs to be recharged. The file ­Tablets contains the battery life of 12 WiFi only and 7 3G/4G/ WiFi 9 through 12 inch tablets.

a. Assuming that the population variances from both types of ­tablets are equal, is there evidence of a difference in the mean battery life between the two types of tablets? 1Use a = 0.05.2

b. Determine the p value in (a) and interpret its meaning.

c. Assuming that the population variances from both types of ­tablets are equal, construct and interpret a 95% confidence ­interval estimate of the difference between the population mean battery life of the two types of tablets.