How many product-related factors are there to influence the transport cost? （） Four 。 Three 。 Two 。 Five。
Which mode of transportation is most flexible? （） Air 。 Ship 。 Rail 。 Motor。
What is SCM? （） Supply Customer Management。 Support Customer Management。 Supply Chain Materials。 Supply Chain Management。
What is the meaning of integration? （） To link some separate factors as a whole chain。 United。 To put together。 Mixture。
How many flows are there in global logistics?（） One。 Two。 Four。 Three。
What is PDM?（）
