Question: The associated Insurance Institute sponsors studies of the effect of drinking on driving. In one such study, three groups of adult men were randomly selected for an experiment designed to measure their blood alcohol levels after consuming five drinks. Members of group A were tested after 1 hour, member of group B were tested after 2 hours, and members of group C were tested after 4 hours. The results are given in the accompanying table; the minitab display for these data is also shown. At the 0.05 significance level, test the claim that the three groups have the same mean level.

Minitab:

Source DF SS MS F P

Factor 2 0.0076571 0.0038286 46.90 0.000

Error 14 0.0011429 0.0000816

Total 16 0.0088000