What is the result？（）

A、 Compilation fails.

B、 An exception is thrown at runtime.

C、 The variable first is set to null.

D、 The variable first is set to elements[0].

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  C、P（S1）、V（S2）

  D、P（S2）、V（S1）

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• Which of the following would help a new administrator quickly determine if a network had a VLANfor its publicly accessible servers?（）

  A、Baselines

  B、Regulations

  C、Logical network diagrams

  D、Wiring schematics

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• You want to enable archiving on your database. Presently， the database is running in NOARCHIVELOG mode.Given below are the steps to accomplish the task in random order： 1. Shut down the instance. 2. Execute the ALTER DATABASE ARCHIVELOG command. 3. Start up the instance and mount the database. 4. Set the DB_RECOVERY_FILE_DEST initialization parameter to $ORACLE_HOME/dest_1. 5. Open the database. Which is the correct sequence of steps for accomplishing the task（）

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  C、1， 3， 2， 5； 4 not required

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• Identify the three predefined server-generated alerts. （） 

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• Mary has a view called EMP_DEPT_LOC_VU that was created based on the EMPLOYEES, DEPARTMENTS, and LOCATIONS tables. She granted SELECT privilege to Scott on this view. Which option enables Scott to eliminate the need to qualify the view with the name MARY .EMP_DEP_LOC_VU each time the view is referenced?（）

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