患者感到呼吸困难，其呼吸困难的特点为

Which of the following types of change is gradual, incremental, and narrowly focused？

A．Infrastructure change

B．Structural change

C．Revolutionary change

D．Evolutionary change

L 0 DATABASE;The next day, you issue the following command:BACKUP INCREMENTAL LEVEL 1 CUMULATIVE DATABASE;Which statement about the use of the change tracking file is true？（）

A. RMAN reads the block change tracking file only when it performs the incremental level 0 backup.

B. RMAN reads the block change tracking file when it performs both incremental backups.

C. RMAN reads the block change tracking file only when it performs the incremental level 1 backup.

D. RMAN does not read the block change tracking file when it performs either incremental backup.

EL 0 DATABASE;To enable block change tracking after the incremental level 0 backup, you issued this command:SQL > ALTER DATABASE ENABLE BLOCK CHANGE TRACKING USING FILE ‘ /mydir/rman_change_track.f’;To perform an incremental level 1 cumulative backup, you issued this command:RMAN> BACKUP INCREMENTAL LEVEL 1 CUMULATIVE DATABASE;Which three statements are true？（）

A. Backup change tracking will sometimes reduce I/O performed during cumulative incremental backups.

B. The change tracking file must always be backed up when you perform a full database backup.

C. Block change tracking will always reduce I/O performed during cumulative incremental backups.

D. More than one database block may be read by an incremental backup for a change made to a single block.

E. The incremental level 1 backup that immediately follows the enabling of block change tracking will not read the change tracking file to discover changed blocks.

Not everyone can perceive the gradual change in the writer’s style．

A．appreciate

B．notice

C．describe

D．recover

Not everyone can perceive the gradual change in the writer’s style．

A．appreciate

B．notice

C．describe

D．recover