A. Flash recovery area must be defined
B. Undo retention guarantee must be enabled.
C. Database must be running in archivelog mode.
D. Automatic undo management must be enabled.
E. The tablespace in which the Flashback Data Archive is created must have automatic segment space Management (ASSM).

A. The data file backup is done with multiple channels
B. The data files is in the read-write mode after being backed up in the read only mode
C. The backup was taken after the data files was taken offline-normal or is in the read only mode
D. The data file backup complies with the back retention policy and the backup duplexing feature