易行线、难行线
参考答案：
调车场的线路由于道岔、曲线、坡度等因素，对溜入的车辆产生阻力，阻力较小容易走行的线路称为易行线，反之为难行线。
A client who agreed to become an organ donor is pronounced dead. What is the most important factor in selecting a transplant recipient ？（）
A．Blood relationship.
B．Sex and size.
C．Compatible blood and tissue types.
D．Need.
电压互感器、电流互感器、避雷器接地引下线与地网应有（）处连接。
A.3
B.2
C.1
D.0
