The function is , where is number of years since .

(a)

Estimate the amount of bottled water consumed in .

The year represents .

Observe the graph :

Approximately  millions of gallons water consumed in .

(b)

Find consumption algebraically.

Find .

.

Round to the nearest ten million gallons.

consumption is million gallons.

(c)

Observe the graph:

Water consumption was billion gallons at .

The year represents .

Confirm algebraically:

Find .

In the year water consumption was billion gallons. 

(a). millions of water consumed in .

(b). consumption is million gallons.

(c). In the year water consumption was billion gallons.