Answer:
Main idea of the text:
Gasoline, diesel, and biodiesel can all be used to run an automobile, however, they are comprised of different substances and can't be used interchangeably to power every automobile.
An appropriate title:
Understanding How Gasoline, Diesel, and Biodiesel differentiate.
Explanation:
The passage contains several key points to understand.
One being the types of fuel, the second being <em>how</em> they power an automobile. Additionally, their flammability, what they are made out of, and how you shouldn't use them interchangeably are all stated. The main idea is the combination of these key points to portray the specific conclusion gathered from the passage.
Voters choose representatives, who in turn… choose their voters.
What is the primary purpose of these stage directions?