多项选择题
A.国有独资公司B.个人独资企业C.国有企业、上市公司D.公益性的事业单位
A.increases as GNP increasesB.is reduced by credit cardsC.decreases as the average selling price of a unit of output increasesD.both A and B
A.主要频率成分B.幅值的大小C.相位D.位移E.速度