Final answer:
The rate of change of area codes in the United States from 1996 to 1999 is 38 area codes per year. The calculated value does not match any of the provided options.
Step-by-step explanation:
To find the rate of change of the number of area codes in the United States from 1996 to 1999, we need to use the formula for rate of change which is given by:
Rate of Change = (Change in Value) / (Change in Time)
In 1996, there were 171 area codes, and in 1999, there were 285 area codes. The change in the number of area codes over this period is:
285 (in 1999) - 171 (in 1996) = 114
The change in time is:
1999 - 1996 = 3 years
So, the rate of change per year is:
114 / 3 = 38
However, this value does not match any of the options given (A) 57 (B) 42 (C) 26 (D) 114. It is possible there may have been an error in the question or in the options provided, as the correct rate of change calculated is 38, which is not listed as an option. Therefore, based on the calculations made, no option is correct.