Explanation:
If you are splitting a partition, the list of values in the VALUES clause applies to the first partition defined. All the remaining states not included in the VALUES clause will be included in a new partition called REGION_SOUTH_EAST.
Incorrect Answers:
1: The REGION_SOUTH_EAST partition will stay in the same tablespace where REGION_EAST partition is located. Only the REGION_NORTH_EAST partition will be created in the TBS2 tablespace.
2: The statement will not fail. The REGION_SOUTH_EAST partition will keep all values of REGION_EAST partition not included into the REGION_NORTH_EAST partition.
3: The REGION_SOUTH_EAST partition will keep all values of REGION_EAST partition not included into the REGION_NORTH_EAST partition, but it will not store rows with a NULL value in the current REGION_EAST partition..
4: The REGION_SOUTH_EAST partition will not use the storage characteristics inherited from the LOCATIONS table.
Reference:
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 134-136
Chapter 3: Manageability Enhancements
Oracle 9i New Features, Robert Freeman, p. 102-108
Chapter 4: New Oracle9i Database DDS and Data-Warehouse Features

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