**Solutions
to Auto CO2 Study**

**Gasoline
Consumption**

In the first
module of this study, total gasoline consumption rate is determined
using three factors: number of vehicles, average miles driven
per year per vehicle, and fuel efficiency. Using data from selected
years between 1980 and 1997, the following functions were computed.

The rate of
gasoline consumption at time *t* was approximated by the
function

The data and
regression for each factor is shown below.

#### Number of
Vehicles

#### Average Miles
Drive

#### Average Fuel
Efficiency

### Carbon Dioxide
Emission

In the second
module of this study, a function describing carbon dioxide emission
from passenger vehicles was constructed. The function was determined
by multiplying the gasoline consumption function from Module 1
by 19.6, the constant rate of CO2 emission per gallon of gasoline
burned.

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