Burning one gallon of gasoline in a car releases approximately 20 pounds of
co2 into the atmosphere.
one person drives 60,000 miles in a car that averages 30 miles per gallon (mpg), while another person drives 60,000 miles in a car that averages 20 mpg. over the course of the 60,000 miles, how many fewer pounds of co2 are released by the 30 mpg car than by the 20 mpg car?