混合成本
参考答案：
指介于固定成本和变动成本之间，其总额既随业务量变动又不成正比例的那部分成本。
下列哪个英语单词的不定冠词应该用“an”（）。
A.shirt
B.coat
C.cake
D.egg
Price discrimination is most accurately defined by which of the following Price discrimination is the practice of charging different consumers different prices for:（）
A. similar products that have identical per-unit production costs.
B. products that have identical price elasticities of demand.
C. the same product or service.
