Two transactions T1 and T2 are given as T1 : r1 (X) w1 (X)r1 (Y)w1 (Y) T2 : r2(Y) w2 (Y)r2 (Z) w2 (Z)where ri (V) denotes a read operation by transaction Ti on a variable V and wi (V) denotes a write operation by transaction Ti on a variable V. The total number of conflict serializable schedules that can be formed by T1 and T2 is __________.

Two transactions T1 and T2 are given as T1 : r1 (X) w1 (X)r1 (Y)w1 (Y)

1.	Two transactions T1 and T2 are given as T1 : r1 (X) w1 (X)r1 (Y)w1 (Y) T2 : r2(Y) w2 (Y)r2 (Z) w2 (Z)where ri (V) denotes a read operation by transaction Ti on a variable V and wi (V) denotes a write operation by transaction Ti on a variable V. The total number of conflict serializable schedules that can be formed by T1 and T2 is __________.
A.	27
B.	23
C.	54
D.	45
Answer» D. 45

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