interview question on deal lock

[sql]

Hi all,
Today , I wan to interview, one of the questions is
ho wto schedule can avoid dead lock.
1) a read lock on tabe T
2) opear a read lock on table T
3) write lock on table T
4) operate a write lock on table T

for my understand deal lock is two process, 1)lock table a , 2)also lock a, 1) wait 2 to release lock inorder to finish the job. and 2 wait 1 to realease to lock to finish his job. do read and write will has any deal lock.

how shoul dI answer this question?
Thnak you
________
Starcraft ii replays