Explanation:
To open the database in the MOUNT stage you can use next three options: issue SHUTDOWN NORMAL and STARTUP MOUNT commands, issue SHUTDOWN IMMEDIATE and STARTUP MOUNT commands, issue SHUTDOWN TRANSACTIONAL and STARTUP MOUNT commands.
Incorrect Answers:
1: The database needs to be shut down before opening in MOUNT stage.
2: The database needs to be shut down before opening in MOUNT stage.
3: STARTUP command will MOUNT and OPEN the database, but we need only MOUNT stage.
4: After SHUTDOWN ABORT command database needs to be recovered and only after that it can be MOUNTED.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 586-591
Chapter 12: Overview of Backup and Recovery

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