The fastest database backup is achieved via InfiniBand.
RMAN does not back up directly to tape.
However, it will integrate with media management software such as Oracle Secure Backup and utilize their capabilities to manage tape libraries.
Exadata Database Machine: The Database Machine contains the databases that need to be backed up.
Oracle RMAN is the only mechanism to back up the databases that utilize
Exadata Storage Servers as the storage.
RMAN processes run on the database servers and interact with the Oracle Secure Backup (OSB) agent, which further interacts with the media management software and enables RMAN to communicate with the tape library.
References: http://apprize.info/data/oracle_4/6.html

Determine the Amount of Available Space
To increase the size of the disks in a disk group you must either have unallocated disk space available, or you have to reallocate space currently used by a different disk group.
Example: View the space currently used by the disk groups.
SELECT name, total_mb, free_mb, total_mb - free_mb used_mb, round(100*free_mb/total_mb,2) pct_free FROM v$asm_diskgroup ORDER BY 1;

The example above shows that the DATAC1 disk group has only about 15% of free space available while the RECOC1 disk group has about 87% free disk space. The PCT_FREE displayed here is raw free space, not usable free space. Additional space is needed for rebalancing operations.
References: http://docs.oracle.com/cd/E80920_01/SAGUG/exadata-administering-asm.htm#SAGUG20526

Explanation/Reference:
The number of failure groups equals the number of Exadata Cells. Each failure group is composed of a subset of grid disks in the Oracle ASM disk group that belong to a single storage cell.
References: http://docs.oracle.com/cd/E80920_01/SAGUG/exadata-administering-asm.htm

A: Creating a Table with Advanced Row Compression
The following example enables advanced row compression on the table orders:
CREATE TABLE orders ... ROW STORE COMPRESS ADVANCED;
B: ARCHIVE LOW compression (Exadata only), recommended for Archival Data with Load
Time as a critical factor

Explanation/Reference:
Automatic Diagnostic Repository Command Interpreter (ADRCI) can be used on an Exadata storage server.
Incorrect Answers:
A: The diskmon process is a fundamental component of Oracle Exadata Storage Server Software, and is responsible for implementing I/O fencing. The process is located on the database server host computer, and is part of Oracle Clusterware Cluster Ready Services (Oracle Clusterware CRS).
D, E: Oracle Virtual Machine (OVM) runs on the database servers.