Explanation:
You use the ALTER TABLE statement to change the PCTFREE value for both FREELIST segments (manual space-managed) and ASM segments. In the case of automatic spacemanaged tables, the ALTER TABLE command does not update the BMBs. Hence, these blocks may not track the true current status of the datablocks. Oracle9i has added a new procedure called SEGMENT_FIX_STATUS to the DBMS_REPAIR package to fix this problem.
Incorrect Answers:
1: Oracle9i has enhanced the DBMS_SPACE package by adding the SPACE_USAGE procedure to obtain information about the free blocks in automatic space-managed (ASM) segments. But you cannot change the PCTFREE value for the table with this package.
3: You cannot change the PCTFREE value of automatic space-managed segments with ALTER command. It can be done with DBMS_REPAIR package.
4: It is possible to change the PCTFREE value of automatic space-managed segments with DBMS_REPAIR package.
Reference:
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 138-142
Chapter 3: Manageability Enhancements
Oracle 9i New Features, Robert Freeman, p. 53-54
Chapter 2: Oracle9i Architecture Changes

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