You plan to execute the following command to perform a Flashback Database operation in your database: SQL> FLASHBACK DATABASE TO TIMESTAMP (SYSDATE -5/24); Which two statements are true about this?（）

A、The database must have multiplexed redo log files

B、The database must be in the MOUNT state to execute the command

C、The database must be in the NOMOUNT state to execute the command

D、The database must be opened in RESTRICTED mode before this operation

E、The database must be opened with the RESETLOGS option after the flashback operatio