Backfat thickness is a variable used in evaluating the meat quality of pigs. An animal scientist measured backfat thickness (cm) in pigs raised on two different diets, with the results given in the table.

Consider using the t test to compare the diets. Bracket the P-value, assuming that the number of pigs on each diet was
(a) 5
(b) 10
(c) 15
Use n1 + n2 - 2 as the approximate degrees of freedom.

Diet Diet 2 3.49 3.05 0.40 0.40