The following data summarize the results from an independent-measures study comparing three treatment conditions.

a. Use an ANOVA with a = .05 to determine whether there are any significant differences among the three treatment means. Note: Because the samples are all the same size, MSwithin is the average of the three sample variances.
b. Calculate h2 to measure the effect size for this study.

M=2 n= 10 T=20 52 = 2.67 M=3 n= 10 T= 30 52 = 2.00 M=4 n=10 T = 40 S2 = 1.33