An experiment was carried out to compare the wear resistance of two different materials for making the soles of children's shoes. Special pairs of shoes were made up with one shoe sole in Material A and the other in Material B. (Either the right or the left shoe was chosen at random to have the Material A sole.) Children were then given the shoes and asked to wear them normally for two months. At the end of that time, the amount of wear (in mm) of each sole was measured, at the centre of the sole.

The differences in wear amounts (Material A - Material B) were calculated. In all there were 13 pairs of shoes. The sample mean of the differences was 0.908 mm, and the standard deviation of the differences was 0.343 mm. Using a method based on the matched-pairs t-test, calculate a 95% confidence interval for the difference between the mean wear amounts for the two materials. Round the end points of your interval to three decimal places and choose the appropriate option.

Select one:

(0.722, 1.094)

(0.813, 1.003)

(0.809, 1.007)

(0.701, 1.115)

(0.692, 1.124)

(0.236, 1.580)

(0.161, 1.655)

(0.703, 1.113)