With reference to Exercise 12.9, determine individual \(95 \%\) confidence intervals for the differences of mean reaction times.

Data From Exercise 12.9

12.9 To find the best arrangement of equipment at the rear of a fire truck, 3 different arrangements were tested by simulating a fire condition and observing the reaction time required to extinguish the fire. The reaction time (in seconds) of 24 firefighters (randomly assigned to the different arrangements) were as follows: Arrangement 1: 40 35 30 32 34 29 36 Arrangement 2: 34 30 28 35 39 28 39 42 38 27 Arrangement 3: 28 35 39 26 31 30 28 Test at the level of significance = 0.05 whether we can reject the null hypothesis that the differences among the arrangements have no effect.