Which three statements are true about undo management in a RAC environment?

You can dynamically assign a newly created undo tablespace to an instance.

In a policy-managed RAC database, an undo tablespace may automatically be created if OMF is enabled for the database.

An instance that performs instance recovery can write to the undo tablespace of a failed instance.

A mixture of automatic undo management and manual undo management is supported within a RAC database.

It is necessary to assign a specific undo tablespace to a specific instance.