Arandom number generator assigned each pepper to one of two groups. the weights of the peppers in each group, given three randomizations, appear in the tables.

first randomization
group a group b
13.6 9.2
12.1 8.2
15.9 11.5
11.2 13.8
9.7 14.6
second randomization
group a group b
8.2 12.1
13.8 14.6
15.9 13.6
9.2 11.2
9.7 11.5
third randomization
group a group b
8.2 12.1
9.7 13.8
11.5 13.6
14.6 11.2
15.9 9.2
for each table, calculate the mean weight for each group, and , and find the difference of the mean of group a and the mean of group b

after the first randomization, is
, is
, and () is
.
after the second randomization, is
, is
, and () is
.
after the third randomization, is
, is
, and () is
.