Hi I need someone to solve me this question

1. Let a database contain initial values x=3,y=6,z=9 Suppose the loggingand-recovery scheme uses deferred update, the log can contain only the after-image values, that is, log records for write_item operations have only a single value. The new value of database element written. let the log contain the sequence of records: [Checkpoint] [start_transaction, T1] [write_item, T1,x,6] [write_item, T1,y,9] [commit, T1] [start_transaction, T2] [write_item, T2,x,9] [start_transaction, T3] [write_item, T3,y,12] [write_item, T3,z,12] [commit, T3] [write_item, T2,y,3] Determine all the possible values of data items x,y, and z that might be written on disk during the execution of the above log operations. a) x=6,y=3,z=9 b) x=9,y=9,z=12 c) x=6,y=12,z=9 d) x=3,y=3,z=12