A sample of 25 concession stand buys at the October 22 matinee of Bride of Chucky showed mean purchase of $5.29 with standard deviation of $3.02. For the October 26 evening showing of same movie, for a sample of 25 buys the mean was $5.12 with standard deviation of $2.14. The means appear to be very close, but not the variances. At a = .05, is there difference in variances? Show all steps clearly, comprising an illustration of decision rule.