按照马氏规则，加氯化氢的产物为

单项选择题Z plc makes a single product which it sells for 76,800 per month and the product has a contribution to sales ratio of 40%. In a period when actual sales were $224,000, Z plc's margin of safety, in dollars, was ( )Z plc 生产单一产品，每单位售价为 16 美元。固定成本为每月 76，800 美元，产品的边际贡献率为 40%。在实际销售额为 224，000 美元时，Z plc 的安全边际销售额是 ( )A.2,500 B.22,000 C.16,000 D.32,000

单项选择题Let R be an asymmetric relation. Which statement about R is right? ( ) A、 B、 C、 D、R is antisymmetric