Submitted by: Alasdair Monro, UK

Answer:
As a rough estimate, the burning of one gallon of gasoline produces about 20 pounds of CO2.  Hence, if you drive 10,000 miles and your car averages 25 miles per gallon of gasoline, it will liberate approximately 8,000 pounds of CO2 to the atmosphere: (10,000 miles) * (1 gallon of gas / 25 miles) * (20 pounds of CO2 / gallon of gas) = 8,000 pounds of CO2.  If your car travels at 50 miles per gallon of gasoline, however, it would liberate only half as much CO2, or 4,000 pounds, in travelling 10,000 miles.

Also,as a rough estimate, a person exhales about 2.2 pounds of CO2 per day; so over a year, a person would exhale approximately 800 pounds of CO2: (2.2 pounds of CO2 / day) * (365 days) = 803 pounds of CO2.