由于计算机系统导致调度自动化系统主要功能失效,单机系统失效时间()者,应定为异常。
A、超过8h;
B、超过12h;
C、超过24h;
D、超过48h。
参考答案:B
Free medical treatment in this country covers sickness of mind as well as ______ sickness. [ ]
A. normal
B. average
C. regular
D. ordinary
基尔霍夫第一定律只能用于节点,不能用于闭合面。()