Actions: \begin{tabular}{|l|l} \hline Say X is branch balance: & write X \\ T1: ... update X... & output X \\ T2: ... update X... & write X \\ T3: ... update X... & output X \\ T4: ... update X... & write X \\ & output X \\ & write X \\ & output X \end{tabular} Task 5 We are using undo/redo logging to recover the database after a system crash. The log on the disk looks like the following: How to recover the database (do you redo, undo, or ignore T1,T2,T3, and T4 )? and what are the values of A,B,C, and D before and after the recovery (if the value is unsure, type "unknown")? Please fill the two tables below