Explanation:
If a database in ARCHIVELOG mode to use recovery manager the target database must be MOUNTED for restriction of data files. Also DBA can only use backups were taken or registered with recovery manger for restore purposes.
Incorrect Answers:
3: Recovery manager can be also used with a database running in NOARCHIVELOG mode.
4: For full recovery of a database not in NOARCHIVELOG mode recovery catalog is not mandatory.
5: There is no PARTIAL RECOVER command used in RMAN.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 683-686
Chapter 14: Database Failure and Recovery

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