A study investigated the effects of physical fatigue on the performance of professional tennis players. Researchers measured the number of unforced errors committed by a random sample of 12 professional tennis players during the first three sets of a match. They hypothesized that increased fatigue would be associated with a greater number of errors. The following is an F-table for this hypothetical study using the one-way within-subjects ANOVA.

Source of Variation	SS	df	MS	Fobt
Between groups			10
Between persons			4
Within groups (error)	55
Total

(a) Complete the F-table.

Source of Variation	SS	df	MS	Fobt
Between groups			10
Between persons			4
Within groups (error)	55
Total

Make a decision to retain or reject the null hypothesis. (Assume alpha equal to 0.05.)