分类代号为QS的控制类工具,其工具特征是()。
A.固定
B.活动
C.侧孔
D.桥式
参考答案:D
交货率是指实际交货数占全部订货数的比例。()
()is the sending and receiving of the messages by computer. It is a fast, low-cost way of communicating worldwide.
A.LAN
B.Post office
C.E-Mail
D.Interface