$\"\"$

(a)

The first restaurant can be modeled by $\"\"$ .

The second restaurant can be modeled by $\"\"$ .

Where t = 3 represents 2003.

The function $\"\"$ represents the total sales of the two restaurants.

The third restaurant can be modeled by $\"\"$ .

$\"\"$

$\"\"$ .

The third restaurant can be modeled by $\"\"$ .

$\"\"$

(b)

The functions are $\"\"$ , and $\"\"$ .

Graph :

$\"graph$

$\"\"$

(a)

The third restaurant can be modeled by $\"\"$ .

(b)

Graph :

$\"graph$