Which three statements are true about System Global Area (SGA)?

SGA contains shared memory structures for all Oracle processes running on a single server.

Each server process has its own SGA.

SGA is allocated automatically when a database is started.

SGA is used to speed up queries by caching data blocks, program data, information about database objects, and query results

SGA is allocated automatically when a database is mounted.

SGA is read and written by server and background processes.