Answer: c. There is sufficient evidence to support the claim that the mean is greater than 23 miles per gallon.
Step-by-step explanation:
When doing a research, there are 2 Hypothesis one must come up with which are the Null Hypothesis and the Alternative hypothesis.
The Null Hypothesis should state that there is no relationship between the variables which in this case would mean that new sedan, the Libra, will not average better than 23 miles per gallon in the city.
The Alternative Hypothesis on the other hand affirms the belief of the researcher which in this case is that new sedan, the Libra, will average better than 23 miles per gallon in the city.
As the null hypothesis was rejected by the evidence, it means that indeed the Libra mean is greater than 23 miles per gallon.