Answer:
1.0236 billion metric tons
Step-by-step explanation:
Given Parameters
Number of cars = 300000000
Average gas mileage per car = 25 MPG
Average distance covered by a car in one year = 10000 miles
CO2 Emission = 8.53 kg/gallon
Derivations from the given parameters,
If the average gas mileage per car is 25 MPG, then the volume of fuel consumed by a car in a year is:
10000 miles ÷ 25 MPG = 400 gallons
The CO2 emission for one car in a year is:
400 gallons × 8.53 kg/gallon = 3412 kg or 3.412 metric tons (note: 1000 kg = 1 metric ton)
The CO2 emission for 300000000 cars in year is:
3.412 metric tons × 300000000 = 1023600000 kg = 1.0236 billion metric tons