1.【答案】A。
解析：Step fixed cost呈阶梯状上升的固定成本。
知识点：Cost behaviour patterns (Chapter 4 Cost behaviour)
2.【答案】A。
解析：用High-low method把variable and fixed element拆分出来。
Variable cost = (31,046-28,176)/(6,340-5,520)=$3.5 per unit
Fixed cost = $31,046-3.5×6,340=$8,856
知识点：Determining the fixed and variable elements of semi-variable costs (Chapter 4 Cost behaviour)
