渠道长度
参考答案：企业在纵向上所配置的不同类型的中间商的数目。
下列制成物品所使用的材料，属于无机非金属材料的是[ ]
A.
B.
C.
D.
My best friend Alex failed in the math competition. I'd like to_________.
A. dress him up B. pick him up C. cheer him up
