5. The moving average in forecasting is useful because it: A) eliminates the trend. B) smooths the random fluctuations. C) counteracts the seasonal variations. D) approximates the period average. 6. Which of the following describes seasonal variations in a time series? A) The long-run general movement in a time series (e.g, sales) B) Variations in a time series which recur but are not periodic C) Movement of 7 periods or more D) Often caused by economic expansions and contractions E) Recurring and periodic (i.e.), possessing a regular period variation in a time series