Consider the following log:

LSN	LOG
00	begin_checkpoint
10	end_checkpoint
20	update: T1 writes P1
30	update: T1 writes P2
40	update: T2 writes P3
50	update: T3 writes P4
60	T1 commit
70	update: T3 writes P2
80	T1 end
90	update: T2 writes P1
100	T2 commit
	CRASH, RESTART

In this log, we store information about 3 transactions. After the log record with LSN 100, the system crashes and then we restart. We use the ARIES recovery algorithm. Based on this algorithm, answer the following questions:

a) What is done during the Analysis phase?

b) What is done during the Redo phase?

c) What is done during the Undo phase?

d) Show the log when recovery is complete, including all non-null prevLSN and undonextLSN values in log records.