Nate     Natalie
  5_2        2_2
10_4        4_4
15_6        6_6
Natalie walked 6 feet
        
                    
             
        
        
        
The average rate of change of a function f(x) over an interval (a, b) is given by 

Therefore, given a function, f(x), over an interval (2, 9), the average rate of change of the function can be found using the expression
 
 
        
        
        
Answer:
1). Because whole number doesn’t allow decimal numbers.
2). Because whole number doesn’t allow negative numbers. It starts with 0, 1, 2, 3....