Estimate the number of gallons of gasoline consumed by the total of all automobile drivers in the United States, per year.

Estimate the number of gallons of gasoline consumed by the total of all automobile drivers in the United States, per year. Assume there are about 300,000,000 people in the United States, half of them have cars, they each drive 11,000 miles per year, and their cars get 22 miles per gallon of gas.