Java in the Database ? 1
Optimizer and Query ? 7
Summary Management ? 6 (Easy)
Indexes and Index-Organized Tables ? 3
Object Relational Features and LOBS ? 3
Partitioning Improvements ? 6 (Easy)
Oracle Universal Installer : Migration and Upgrade ? 3
Tablespace Management ? 6
Database Resource Manager ? 2 (Difficult)
Manageability Enhancements ? 3
Availability and Recoverability Enhancements ? 8 (Difficult)
Features of NET8 ? 1 (Difficult!)
SQL*Plus, Pl/SQL, & National Language Support Enh ? 3
Database Security ? 2

By the way, since it is very hard to prepare for all materials, you will definitely meet some questions that you've never seen before, I supply some tips for guessing answers:

1. choose LONGER answer(s)
2. choose the answer in which some specific word(s) repeat most times
3. choose C
4. choose B

Note: use the above tips on your own risks.