单项选择题
（）is the way to deliver goods for different shippers in the same truck by the most economic route.
A.Joint distribution B.United distribution C.Multiple deliveries D.joint delivery
单项选择题 （）is not a physical wall but a flow virtual data to protect the computer network.
单项选择题 （）means to provide facility for customer’s need or inquiry and arrange it.
单项选择题 Saving or reducing expenditure in business is（）
