You have the following data for the last 12 months' sales for the PRQ Corporation (in thousands of dollars):
January 500 July 610
February 520 August 620
March 520 September 580
April 510 October 550
May 530 November 510
June 580 December 480
a. Calculate a 3-month centered moving average.
b. Use this moving average to forecast sales for January of next year.
c. If you were asked to forecast January and February sales for next year, would you be confident of your forecast using the preceding moving averages? Why or why not?