Rewrite the following paragraph to increase clarity and conciseness. The automobile is propelled by an internal combustion engine. The engine creates energy by burning gasoline. Gasoline is also called a fossil fuel. Fossil fuels create pollution when burned. The newer automobiles create less pollution than older models. The amount of pollution emitted by autos has decreased greatly in the past thirty years. Automakers have installed pollution control devices on their autos. Oil companies manufacture cleaner burning fuel. This has helped diminish the pollution problem in many urban areas.