a. (8pts) List the four standard necessary conditions of Deadlock. b. (8pts) Let P be a set of processes and R is a set of resources. The set E holds request assignment edges of a process and resource. The sets P, R, and E are as follows: P = {P1, P2, P3} R = {R1, R2, R3} E = {P1->R1, P2->R3, P3->R2, R1->P2, R2->P2, R2->P1, R3->P3} R1 has one instance. R2 has 2 instances. R3 has one instance. Draw the resource allocation graph. c. (4pts) Is there deadlock in this situation? Briefly explain your answer.