A. CPU usage
B. degree of parallelism
C. number of open cursors
D. number of sorts performed
E. idle time for blocking sessions
F. number of disk I/O operations performed
G. number of memory I/O operations performed

A. It keeps track of changes in the background processes.
B. It records the system change number （SCN） in the control file.
C. It writes audit records for user changes to the change tracking file.
D. It records any changes to the listened configuration in the listener.ora file.
E. It records any changes to the database parameters in the change tracking file.
F. It records the physical location of all the changes that are made to the database in the change tracking file.