# Question

The following data describe the monthly volume for an urban courier service. Data are in thousands of pieces handled.

a. Construct a graph of the time series. Does the overall trend appear to be upward or downward?

b. Determine the three-month and five-month centered moving average curves and superimpose each on the original time series.

a. Construct a graph of the time series. Does the overall trend appear to be upward or downward?

b. Determine the three-month and five-month centered moving average curves and superimpose each on the original time series.

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