Explanation:
DB_2K_CACHE_SIZE and DB_4K_CACHE_SIZE parameters are required in order to “plug in” the OLTP tablespaces into the warehouse database. DB_CACHE_SIZE specifies the database buffer cache sized to the standard block size. Oracle 9i can also support four additional block sizes; you can specify the buffer cache size corresponding to each of these block sizes with the DB_nK_CACHE_SIZE parameter. It this parameter, nK stands for the nonstandard block size; n can take the following values: 2, 4, 8, 16, or 32.
Incorrect Answers:
3: The database block size on the data warehouse is 8192, so DB_8K_CACHE_SIZE does not need to be specified.
4: There is no DB_2K_BLOCK_BUFFERS parameter in Oracle. You can specify the buffer cache size with the DB_nK_CACHE_SIZE parameter.
5: There is no DB_4K_BLOCK_BUFFERS parameter in Oracle. You can specify the buffer cache size with the DB_nK_CACHE_SIZE parameter.
6: There is no DB_8K_BLOCK_BUFFERS parameter in Oracle. You can specify the buffer cache size with the DB_nK_CACHE_SIZE parameter.
Reference:
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 164-166
Chapter 3: Manageability Enhancements
Oracle 9i New Features, Robert Freeman, p. 14-16
Chapter 1: Oracle9i Database Administration and Management Features

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