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A8. Efficient supply chains will be most preferred when: A. Product variety is high and demand is predictable B. Product variety is high and demand is unpredictable C. Product variety is low and demand is predictable D. Product variety is low and demand is unpredictable A9. A six-month moving average forecast is generally better than a three-month moving average forecast if demand A) is rather stable B) has been changing due to recent promotional efforts C) follows a downward trend D) exceeds one million units per year E) follows an upward trend A10. If two variables were perfectly correlated, the correlation coefficient r would equal to A) O B)-1 C) 1 D) 1 or -1 E) none of the above