27. A manufacturer claims its Brand A battery lasts longer than its competitor's Brand B battery. Nine batteries of
each brand are tested independently, and the hours of battery life are shown in the table below.
Brand A
Brand B
88
80
85
79
80
77
81
82
72
75
90
81
85
77
85
73
84
78
Provided that the assumptions for inference are met, which of the following tests should be conducted to
determine if Brand A batteries do, in fact, last longer than Brand B batteries?
(A) A one-sided, paired 1-test
(B) A one-sided, two-sample t-test
(C) A two-sided, two-sample t-test
(D) A one-sided, two-sample z-test
(E) A two-sided, two-sample z-test