The data represent the lengths in feet of three types of bridges in the United States. At α = 0.01, test the claim that there is no significant difference in the means of the lengths of the types of bridges.

If the null hypothesis is rejected, use the Scheffé test when the sample sizes are unequal to test the differences between the means, and use the Tukey test when the sample sizes are equal. Perform these steps.
a. State the hypotheses and identify the claim.
b. Find the critical value(s).
c. Compute the test value.
d. Make the decision.
e. Summarize the results, and explain where the differences in means are.
Use the traditional method of hypothesis testing unless otherwise specified.

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