Performance of a turbocharged engine can be improved by（）
A. decreasing the amount of valve overlap
B. preheating the air intake
C. after-cooling the intake air
D. preheating light fuel
The RMAN BACKUP command using the DELETE INPUT option can be used with which three types of files？ （）
A. data files
B. backup sets
C. control files
D. archived redo log file
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