Consumption of Fuels and Their Effects

Q. Which of the following factors influence the properties of fuels?

1. Number of carbon atoms
2. Number of hydrogen atoms
3. Structure of carbon chain
4. Source of the fuel

Q. Fossil fuels are exhaustible natural resources because they:

1. take millions of years to form.
2. cannot be replenished in one human lifespan.
3. can be formed only through a natural process.
4. cause pollution.