Given the following three transactions:
T1 = r1(x); r1(y); w1(z);
T2 = r2(x); w2(x); w2(y);
T3 = r3(y); w3(z);
Consider the schedule:
S = r1(x); r2(x); r3(y); r1(y); w3(z); w2(x); w2(y); w1(z);
a. Use any software to draw the precedence graph of schedule S, and label each edge with data item(s).
b. Based on the precedence graph, determine whether S is conflict serializable and justify your answer.