A consumer preference study compares the effects of three different bottle designs (A, B, and C) on sales of a popular fabric softener. A completely randomized design is employed. Specifically, 15 supermarkets of equal sales potential are selected, and 5 of these supermarkets are randomly assigned to each bottle design. The number of bottles sold in 24 hours at each supermarket is recorded. The data obtained are displayed in the following table.

Bottle Design Study Data
A	B	C
	13			29			28
	16			35			27
	16			31			22
	14			29			26
	14			31			26

The Excel output of a one-way ANOVA of the Bottle Design Study Data is shown below.

SUMMARY
Groups	Count	Sum	Average	Variance
Design A	5	73	14.6	1.8
Design B	5	155	31.0	6.0
Design C	5	129	25.8	5.2

ANOVA
Source of Variation	SS	df	MS	F	P-Value	F crit
Between Groups	702.4000	2	351.2000	81.05	3.23E-06	3.88529
Within Groups	52.0	12.0	4.3333
Total	754.4000	14

(a) Test the null hypothesis that _A, _B, and _C are equal by setting = .05. Based on this test, can we conclude that bottle designs A, B, and C have different effects on mean daily sales? (Round your answers to 2 decimal places. Leave no cells blank - be certain to enter "0" wherever required.)

F
p-value

(Click to select) Reject Do not reject H₀: bottle design (Click to select) does does not have an impact on sales.

(b) Consider the pairwise differences _{B A}, _{C A} , and _{C B}. Find a point estimate of and a Tukey simultaneous 95 percent confidence interval for each pairwise difference. Interpret the results in practical terms. Which bottle design maximizes mean daily sales? (Round your answers to 2 decimal places. Negative amounts should be indicated by a minus sign.)

Point estimate Confidence interval

_{B A}: , [, ]

_{C A}: , [, ]

_{C B}: , [, ]

Bottle design (Click to select) C A B maximizes sales.

(c) Find a 95 percent confidence interval for each of the treatment means _A, _B, and _C. Interpret these intervals. (Round your answers to 2 decimal places. Negative amounts should be indicated by a minus sign.)

Confidence interval

_A: [, ]

_B: [, ]

_C: [, ]