A study was done before the recent surge in gasoline prices to compare the cost to drive 25 miles for different types of hybrid vehicles. The cost of a gallon of gas at the time of the study was approximately $2.50. Based on the information given below for different models of hybrid cars, trucks, and SUVs, is there sufficient evidence to conclude a difference in the mean cost to drive 25 miles? Use α = 0.05.

Assume that all variables are normally distributed, that the samples are independent, and that the population variances are equal. Also, for each exercise, perform the following steps.
a. State the hypotheses and identify the claim.
b. Find the critical value.
c. Compute the test value.
d. Make the decision.
e. Summarize the results, and explain where the differences in the means are.
Use the traditional method of hypothesis testing unless otherwise specified.

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Hybrid cars 2.10 2.70 1.67 1.67 1.30 Hybrid SUVs 2.10 2.42 2.25 2.10 2.25 Hybrid trucks 3.62 3.43