Engineers are testing company fleet vehicle fuel economy (miles per gallon) performance by using different types of fuel. One vehicle of each size is tested. Does this sample provide sufficient evidence to conclude that there is a significant difference in treatment means? 87 Octane___89 Octane___91 Octane___Ethanol 5%___Ethanol 10%
Compact29.3 25.6 27.226.8 25.8
Mid-sized28.6 25.6 24.2 26.6 23
Full-sized21.4 22.523.3 23.9 23.8
SUV21.722.423.1 22.7 24.1

a. State the null and alternative hypotheses (include any and all hypotheses that are necessary).
b. What is the critical value for car size?
c. What is the critical value for fuel type?
d. What is the test statistic for car size?
e. What is the test statistic for fuel type?
f. Do you reject or fail to reject for car size?
g. Do you reject or fail to reject for fuel type?
h. What conclusions can you draw (you should make multiple conclusions is you have multiple sets
of hypotheses).