Oracle Database Discussions

hi,
These are the interview question i got can anyone plz give me the answer.

1).Database is hung. Old and new user connections alike hang on impact. What do you do? Your SYS SQLPLUS session IS able to connect.

2).Database crashes. Corruption is found scattered among the file system neither of your doing nor of Oracle’s. What database recovery options are available? Database is in archive log mode.

3)How does Oracle guarantee data integrity of data changes?

4)How would you go about verifying the network name that the local_listener is currently using?

5)You have 4 instances running on the same UNIX box. How can you determine which shared memory and semaphores are associated with which instance?

6)What is the recommended interval at which to run statspack snapshots, and why?

answers are appriciatable........

with regards
Boo