Every one of us is all too familiar with the phenomenon of forgetting. Facts that we clearly understood at the time we first learned them sometimes fade from our memory by the time the final exam...

Extracted text: Every one of us is all too familiar with the phenomenon of forgetting. Facts that we clearly understood at the time we first learned them sometimes fade from our memory by the time the final exam rolls around. Psychologists have proposed several ways to model this process. To develop her own model, a psychologist performs an experiment on a group of volunteers by asking them to memorize a list of 100 related words. She then tests how many of these words they can recall after various periods of time. The average results for the group are shown in the table. Time Words recalled 15 min 66.3 1 h 47.1 8 h 39.3 1 day 34.8 2 days 28.9 3 days 27.6 5 days 24.9 (a) Use a graphing calculator to find a power function of the form y = atº that models the average number of words y that the volunteers remember after t hours. (Round all values to three decimal places.) Find an exponential function of the form y = ab' to model the data. (Round all values to three decimal places.) y =