You can use Oracle Flashback to look at past activity in your database. What are two other characteristics of Oracle Flashback？（）
A. Oracle Flashback uses undo information to construct consistent data.
B. You can use a cursor opened while using an Oracle Flashback image to perform DML once you deactivate Oracle Flashback in your session.
C. You can only use Oracle Flashback view of the data if the required records are still in the online redo log files.
D. Oracle Flashback lists the DML that was executed during the period you identify when initiating your session.
Given a pre-generics implementation of a method： What three changes allow the class to be used with generics and avoid an unchecked warning？（）
A. Remove line 14.
B. Replace line 14 with "int i = iter.next（）；".
C. Replace line 13 with "for （int i ： intList） {".
D. Replace line 13 with "for （Iterator iter ： intList） {".
E. Replace the method declaration with "sum（List
What is the result？（）
A. Compilation fails.
B. An exception is thrown at runtime.
C. doStuff x=6，main x=6
D. doStuff x=5，main x=5
E. doStuff x=5，main x=6
F. doStuff x=6，main x=5
Given： What is the result？（）
A. Compilation fails due to an error in line 23.
B. Compilation fails due to an error in line 29.
C. A ClassCastException occurs in line 29.
D. A ClassCastException occurs in line 31.
E. The value of all four objects prints in natural order.
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