Explanation:
Database files are backed up using operating system commands if you are using user-managed backup and recovery operations. Recovery is initiated using SQL*Plus. The files that need to be backed up are copied to the desired location, and in the event of a media failure the appropriate files are restored to the original destination and recovered manually using wither SQL*Plus or SQL Worksheet tool. Incorrect Answer:
3: Using user-managed backup and recovery operations you don’t have to work with Recovery Manager.
4: Using user-managed backup and recovery operations you don’t have to work with Recovery Manager.
2: Database files are backed up using SQL*Plus and SQL commands. They just can be copied by using operating system commands.
Reference:
OCP Oracle 9i Database: Fundamentals II Exam Guide, Rama Velpuri, p. 241-244
Chapter 10: User-Managed Backups

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