9 10 10 8 10 9
6 6 5 4 5 7
8 9 8 7 8 7
5 7 7 5 5 6
Here you see taste ratings for 4 cola types: Cola A (A), generic Cola A (GA), Cola B (B), and generic Cola B (GB). L1 is the difference in taste scores between non-generic and generic Colas (nongeneric - generic). What is L1 for the fourth subject?

0
6
0.0
no
(A+B) - (GA + GB) specifically compares non-generic and generic Colas. It is (8 + 7) - (4 + 5) = 6.
Calculate the standard error for L1 (L1 = A + B - GA - GB). Keep in mind this is a repeated-measures design.

0
0.654
0.1
Compute L1 for each subject: (6, 6, 6, 6, 8, 3) and then compute the standard deviation (1.602) which you then divide by the square root of n (n = 6) to get 0.654
Calculate t for L1 (L1 = A + B - GA - GB).

0
8.919
0.05
Compute L1 for each subject: (6, 6, 6, 6, 8, 3) and then compute the mean (5.833) and standard deviation (1.602). You then divide the standard deviation by the square root of n (n = 6) to get the standard error (0.654). Then divide the mean by the standard error to get t = 8.919.