A curvilinear relationship between variable costs and changes in activity levels suggests what? a. Since the relationship between activity levels and variable costs is linear within the relevant range and less linear at lower and higher levels outside the relevant range, the straight-line (linear) relationship takes on a curvature in the real world. b. All of the above. A strictly linear relationship between xed costs and activity levels is implausible. d. A strictly curvilinear relationship between changes in activity levels and variable costs is possible only within the relevant range. Hooter Manufacturing Company reported the following year-end information: Beginning work in process inventory . $75,000 Beginning raw materials inventory ...... 20,000 Ending work in process inventory 73,000 Ending raw materials inventory 23,000 Raw materials purchased 220,000 Direct labour ... 170,000 Manufacturing overhead 80,000 How much is Hooter Manufacturing's cost of goods manufactured for the year? O a. $465,000 b. $470,000 O c. $469,000 O d. $472,000