(a) Draw the precedence graph with the following precedence relation: S1→ S2; S1→ S3; S1→ S4; S2 → S5; S3→ S5; S4 → S6; S5 → S6 Now suppose that we add the edge (S2, S4) to the graph. (i) Can this new precedence graph be expressed using only the concurrent statement? If so, show how, if not, explain why? (ii) How can this precedence graph be expressed if semaphores are also used?
