Final answer:
The federal appellate court is more likely to overturn the EPA's final rule.
Step-by-step explanation:
It is more likely that the federal appellate court will overturn the EPA's final rule. The court will review the EPA's decision and assess whether it is in accordance with the law. In this case, the EPA's interpretation of the Clean Air Act to exclude electric vehicles (EVs) may be subject to challenge as it goes beyond what the statute says, which is silent on the applicability of the Act to EVs. The court will consider the arguments and evidence presented by the manufacturers of gas-powered vehicles and determine whether the EPA's decision is reasonable and supported by the law.