Three brands of batteries are under study. It is suspected the lives of the three brands are different. An experiment is conducted to test the hypothesis. Five random batteries of each brand are selected. The time (in hours) until the battery is effectively dead (when power output drops below a specified level) is measured for each battery. Which hypothesis test would be most appropriate for this study? Group of answer choices One mean (sigma known) - one sample z One mean (sigma unknown) - one sample t Mean of differences, using dependent samples (paired data) Difference of two means (independent samples) Several means (ANOVA) One proportion