车辆检修车回送单是（），本单编制两份，一份留存，一份随车辆送至到达地点。
A.车统—23
B.车统—24
C.车统—25
D.车统—26
参考答案：D
常用的重垂线的原理是___________________________，生活中的应用有________________（举一例）。
(66) is defined as the buying and selling of products and services over the Internet. It had included the handling of purchase (67) and funds transfers over computer networks from its inception.
A．Electronicmail
B．Searchengine
C．Multimedia
D．Electroniccommerce
