Databases System: The complete book. Exercise 18.2.4. For each of the following schedules:

(a) r1(A); r2 (A); r3 (B); w1>i(A); r2 (C); r2 (B); w2 (B); W1(C);

(b) r1(A); W1(B); r2(B): w2 (C); r3 (C); w3 (A);

(c) r1(A); r2 (A); w1(B); w2 (B); r1 (B ); r2(B); w2 (C); w1(D).

Answer the following question:

i. What is the precedence graph for the schedule?

ii. Is the schedule conflict-serializable? If so, what are all the equivalent serial schedules?

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