由于征税损害了价格作为引导资源有效配置的信号作用,造成的额外的经济效率损失称为()。 ["税收负担","税收负效应","税收的额外负担","税收中性"]
举例说明酵母菌生活史的三个类型。
城市公共交通的性质
What is the result?() ["test","null","An exception is thrown at runtime.","Compilation fails because of an error in line 1.","Compilation fails because of an error in line 4.","Compilation fails because of an error in line 5."]
弹性流体动力润滑的机理
变压器接线组别是指用时钟表示法表示三相变压器()线圈连接方式和它们()相位关系。