Starbucks stores the table gives the total number of Starbucks stores and the total number of U.S. Starbucks stores for selected years since 1992.
![1963_total number of Starbucks stores.png](https://secure.tutorsglobe.com/CMSImages/1963_total number of Starbucks stores.png)
Assume the total number of U.S. stores, y, can be modeled as a function of the total number of stores, x, with the function y = 1.25x0.94
(a) Use this model to find a function that models the instantaneous rate of change of y.
(b) Find a function that models the rate at which the instantaneous rate from part (a) is changing.
(c) Use the results from parts (a) and (b) to find and interpret y'(18,000) and y"(18,000).