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 pet minute Answer the following questions. (b) For which time periods was the person's heart rate decreasing? A. from 1 through 1 1 minutes B. from 3 through 9 minutes and from 11 through 15 minutes C. from 3 through 15 minutes D. from 1 through 3 minutes and from 9 through 11 minutes (C) How many tuning point, (from increasing to decrease or from decrease to increasing) occured for the person's heart rate during the 15 minute film?