The graph to the right shows the heart rate of a person watching a short romantic film, where x represents time in minutes, and y represents heart rate in beats per minute. Answer the following questions. 80- 70- 60- 50- 40- 0 12 16 Z (a) For which time periods was the person's heart rate increasing? OA. from 1 through 5 minutes and from 9 through 12 minutes B. from 5 through 15 minutes C. from 1 through 12 minutes D. from 5 through 9 minutes and from 12 through 15 minutes (b) For which time periods was the person's heart rate decreasing? O A. from 1 through 5 minutes and from 9 through 12 minutes B. from 1 through 12 minutes C. from 5 through 9 minutes and from 12 through 15 minutes D. from 5 through 15 minutes (c) How many turning points (from increasing to decreasing or from decreasing to increasing) occurred for the person's heart rate during the 15 minute film? (d) Suppose that a polynomial function is used to model the data displayed by the graph. What is the degree of the polynomial function of best fit? (Use the number of turning points to determine the degree.) (e) For the model in part (d), should the leading coefficient of the polynomial function be positive or negative? Why A. positive because the graph falls to the left and falls to the right B. positive because the graph falls to the left and rises to the right C. negative because the graph falls to the left and falls to the right OD. negative because the graph rises to the left and falls to the right (f) Use the graph to estimate the person's maximum heart rate during the 15 minute film. bpm After how many minutes did this maximum heart rate occur? minute(s) (g) Use the graph to estimate the person's minimum heart rate during the 15 minute film. bpm After how many minutes did this minimum heart rate occur? minute(s)