5. What 6. D is the relationship between committed resources and cost behavior? escribe ble to the difference between a variable cost and a step-variable cost. When is treat step-variable costs as if they were variable costs? 7. Why do mixed costs pose a problem when it comes to classifying costs into fixed and 8. Why is a scattergraph a good first step in separating mixed costs into their fixed and va 9. What are the advantages of the scatterplot method over the high-low method? The highn 10. Describe the method of least squares. Why is this method better than either the highlo 11. What is meant by the best-fitting line? Is the best-fitting line necessarily a good-itting line able categories? components? method over the scatterplot method? method or the scatterplot method? Explain. riabe 12. When is multiple regression required to explain cost behavior? 13. Explain the meaning of the learning curve. How do managers determine the appropriate learning curve percentage to use? 14. Assume you are the manager responsible for implementing a new service. The time to pr form the service is subject to the learning curve. Would you prefer that the new service have a learning rate of 85 percent or 80 percent? Why? 15. Some firms assign mixed costs to either the fixed or variable cost categories without using any formal methodology to separate them. Explain how this practice can be defended