You set the following parameters in the parameter file and restarted the database: Which two statements are true regarding these parameters after the database instance is restarted?（）

• A、The MEMORY_MAX_TARGET parameter is automatically set to 500 MB
• B、The value of the MEMORY_MAX_TARGET parameter remains zero till it is changed manually
• C、The PGA_AGGREGATE_TARGET and SGA_TARGET parameters are automatically set to zero
• D、The lower bounds of PGA_AGGREGATE_TARGET and SGA_TARGET parameters are set to 90 MB and 270 MB, respectively