下列不属于可变成本的费用是( )。
A.原材料消耗
B.计件工资
C.包装费
D.折旧费
参考答案:C
—Are you hungry now?
—_______. I have just had two bowls of rice.[ ]
A. Not a bit
B. It doesn't matter
C. Not a little
D. I don't mind.
混凝土外加剂的()测定是按GB/T8077执行的。
A、含固量
B、含水量
C、密度
D、PH值