which functions are inverse of each other? Both? Pair 1 only? Pair 2 only? Or neither?

Given f(x) = 17-x^2what is the average rate of change in f(x) over the interval [1, 5]?

Plz me plz i need and plz delte this after answer

At the beginning of the day, stock xyz opened at $6.12. at the end of the day, it closed at $6.88. what is the rate of change of stock xyz? a. 1.17% b. 11.0% c. 12.4% d. 81.5%