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Question 3: Parti Consider that we need to use semaphores to allow the below sequence of processes to execute: P3 P1 P2 P4 When pl finish its execution, p2 can start the execution. Put differently, P2 can start only if pl finish its execution (same applies for P4). When p2 finish its execution then P3 can start and P4 can start. Put differently, P3 can start only if p2 finish its execution (same applies for P4), Write the necessary semaphores and pseudocode to allow this execution sequence. P2 P3 PI P4 Code code code code Part2 Given 3 concurrent processes P1, P2 and P3 we suppose that initially x =10. P1 P2 P3 X++ XX-2 x=x*3; i. List all the possible values for x