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(1) T_{1} \quad T_{2}\begin{array}{ll}R(A) & \\\omega(A) & R(A) \\R(B) & \omega(A) \\\omega(B) & \\& R(B) \\& \omega(B) \\T_{1} &\end{array}As we can see that T_{2} is only dependent on T_{1}, so no circust is formed in dependency graploHence it is conflict seriabizable Serial schedule is\begin{array}{ll}\frac{T_{1}}{R(A)} & T_{2} \\\omega(A) & \\R(B) & \\\omega(B) & R(A) \\& \omega(A) \\& R(B) \\& \omega(B)\end{array}T_{10}TiI1 T_{12} 11R(A)R(B)\omega(A)R(A)\omega(A)R(A)T_{12} is dependent on T_{11} and T_{11} is dependent on T_{10}So if T_{10} fails T_{11} and T_{12} has to be rolled backAnd this is called cascading rollbacksTo avoid this we have to have the rule that a transaction is not allowed to read a data item until the last transaction that has updated the data is committed or aborted ...