开关变位，主站遥信无反应的原因是主站处理信息时丢失；通道故障而丢失；RTU故障，遥信未反应或开关辅助接点接触不良或继电器未动作等。
参考答案：对
One of the greatest benefits of stamp－collecting is that they are based on common interests，________ appearance，age or wealth.
A．other than
B．or rather
C．rather than
D．instead
在下列大田作物中，长日照作物是（）
A.油菜
B.水稻
C.玉米
D.棉花
