please do the following problems and show the work

33. Now, compute the average rate of change of f(r) = -r +4r- -3r + 1 over the interval [1, 1 + h), where h is any small nonzero number. Simplify this expression as much as possible. Why is it important that h be nonzero? 34. In the previous exercise, the value of h could be any small nonzero number. What would happen to the average rates of change if we were to force h to be close to zero? Describe what happens to the secant lines as the run length h approaches zero. 35. Now, let r be any real number and let h be any positive number. Write down a formula for the average rate of change of any function f over the interval [r, r + . Draw a graph to illustrate