You performed a backup of the flash recovery area by using the following command for the first time：
RMAN> BACKUP RECOVERY AREA; 
Which files in the flash recovery area are backed up？（）

多项选择题Youconfiguredtheflashrecoveryareainthedatabase.Whichtwofileswouldyouexpecttofindintheflashrecoveryarea？（）

A.backup pieces
B.control file autobackups
C.copies of all the parameter files
D.trace file generated using BACKUP CONTROLFILE TO TRACE

单项选择题You enabled the flashback logging feature， but you have not specified the location of the flash recovery area.  Which location would be used as the default location for the flash recovery area？（）

A.the location used for control files
B.the location used for redo log files
C.the location set by using $ORACLE_BASE
D.the location set by using $ORACLE_HOME
E.the location set by using CORE_DUMP_DEST
F.the location set by using BACKGROUND_DUMP_DEST