Cost behavior is fundamentally important concept to managerial accounting. The following statements describe various aspects of cost behavior: a. Facility-level costs include production labor, raw materials, and utilities. b. Fixed costs vary in direct proportion to changes in production volume, but are constant when expressed on a per-unit basis. c. The normal range of production expected for a particular product and company is called the relevant range. d. Assumptions about the behavior of fixed and variable costs are expected to hold inside and outside the relevant range. e. Costs that vary, but only with relatively large changes in production volume, are often called step costs. f. The cost equation y = a + bx can be used to describe fixed costs, but not variable costs. Required Indicate whether each of the preceding statements is true or false