The production manager wants to test whether there is a significant difference in the mean number of defective bulbs per 100 bulbs among the three production shifts. A sample of production records showed the following: 6 a.m. - 2 p.m. shift 2 p.m. - 10 p.m. shift 10 p.m. - 6 a.m. shift 16 19 19 21 20 28 20 23 25 22 18 30 18 25 32 17 20 27 Using a = 0.05 significance level