Question: Jeannette Phan is a college student who has just completed her junior year. The following table summarizes her grade point average (GPA) for each of the past nine semesters:
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(a) Forecast Jeannette's GPA for the fall semester of her senior year by using a three-period moving average.
(b) Forecast Jeannette's GPA for the fall semester of her senior year by using exponential smoothing with a = 0.3.
(c) Which of the two methods provides a more accurate forecast? Justify your answer.
(d) If you decide to use a three-period weighted moving average, find the optimal weights that would minimize MAPE. Is this method an improvement over the previous two methods?