来源: 研究所考试-中山经济 科目:经济 问题:Assume that the supply curve of any firm in industry X is S(P)=P/4.if a f irm has 30 units of output, what is its total variable cost? 答案是1800 我的想法当要素产量30，市价为120， 那么我应该要求出Px，才能以Px *X算出tvc 而用p*MPL=PL,我无法求出MPL, 请问这题是这样算的吗，还是没有这么复杂~~~