a) Why we prefer the undo tablespace instead of backup segment. Justify your answer with logical reasoning b) Suppose you want to modify the retention time to manage the long undo tablespace. This can help you to undo a large amount of data. As a DBA, what factor you need to know to modify or increase the undo Retention and how you can implement that factor in oracle 11 g c) Suppose you want to move from one tablespace to another tablespace. How can you automatically switch from one tablespace to another tablespace? Please write the procedure and implement it in oracle 11g. d) Undo statistics are used to tune the undo tablespace. Who can you manage or view the statistics of the undo tablespace what kind of information a undo tale space have? You need to implement the steps in oracle 11g