子管在人(手)孔内应伸出适宜的长度,可为()mm。
A、100~200
B、200~400
C、300~500
D、400~600
主存储器有ROM和RAM,计算机突然停电后,存储信息就会丢失的是()。
A、外存储器
B、只读存储器
C、寄存器
D、随机存储器
现有: class Thread2 implements Runnable { void run() { System.out.print("go "); } public static void main(String [] args) { Thread2 t2 = new Thread2(); Thread t = new Thread(t2); t.start(); } } 结果为:()
A、 go
B、 编译失败
C、 代码运行,无输出结果
D、 运行时异常被抛出
局域网中,常用的网络传输介质有()
A、双绞线
B、同轴电缆
C、光缆
D、电话线
You have enabled backup optimization for the RMAN environment.Identify two criteria on which RMAN will skip the file, if it has already been backed up.()
AThe data file backup is done with multiple channels
BThe data files is in the read-write mode after being backed up in the read only mode
CThe backup was taken after the data files was taken offline-normal or is in the read only mode
DThe data file backup complies with the back retention policy and the backup duplexing feature
下面程序的输出是什么()。
A、342
B、3423
C、34234
D、323