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...

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. (Data extracted from “Ratings and recommendations: Tablets,” Consumer Reports, August 2013, p. 24.)

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.