You have lost datafiles 1 and 3 from your database，and the database has crashed. In what order should you perform the following steps to recover your database？（） 1. Take the datafiles that were lost offline. 2. startup mount the database 3. Issue the alter database open command. 4. Restore the datafiles that were lost 5. Recover the datafiles with the recover datafile command. 6. Bring the datafiles back online. 7. Recover the database with the recover database command. 2，1，3，4，5，6。 2，4，5，3。 4，7，3。 2，4，7，3。 2，7，3。
IT服务的财务周期包括（） 了解对IT服务的业务要求。 IT服务的预算。 IT服务的核算。 对IT服务的计费。
Given a class Repetition: Which code should be inserted at line 1 of Demo.java to compile and run Demo to print "pizzapizza"?（） import utils.*;。 static import utils.*;。 import utils.Repetition.*;。 static import utils.Repetition.*;。 import utils.Repetition.twice();。 import static utils.Repetition.twice;。 static import utils.Repetition.twice。
You issued the following command： ALTER DATABASE ENABLE BLOCK CHANGE TRACKING； What will be the result of issuing this command？（） The block change tracking feature is enabled， and the information about the system change number is written in the change tracking file.。 The block change tracking feature is enabled， and the information about the log sequence number is written in the change tracking file.。 The block change tracking feature is enabled， and the information about the blocks that are changed since the last backup is written in the change tracking file.。 The block change tracking feature is enabled， and the information about the locations of the datafiles and the online redo log files are written in the change tracking file.。
中国银行属于在线中介的类型是（） 接入服务商。 金融中介。 结算/交易处理商。 信息访问提供商。
应退出电压互感器摇测绝缘的情况是（）。
