Explanation:
It’s not possible to take a default temporary tablespace offline. Ther are some other restrictions on the default temporary tablespace: you cannot drop a default temporary tablespace until you have created a new default temporary tablespace; you cannot change a default tablespace into a permanent tablespace; you cannot change a permanent tablespace into a temporary tablespace unless it is the SYSTEM tablespace.
Incorrect Answers:
2: The database should not be quiesced before you take a database default temporary tablespace offline.
3: You don’t need to check that all users are assigned to an alternative temporary tablespace first.
4: The default temporary tablespace cannot have the permanent tablespace characteristic.
Reference:
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 158-160
Chapter 3: Manageability Enhancements
Oracle 9i New Features, Robert Freeman, p. 18-19
Chapter 1: Oracle9i Database Administration and Management Features

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