Consider a system having two resource types rt1 and rt2. let there be two resources of type rt1 and let there be a single resource of type rt2. let p1, p2, p3 and p4 be four processes competing for these resources. in the following sequences of request events, let (pi, rtj) denote a request event indicating that process pi requests a resource of type rtj. consider each sequence of request events and determine whether it causes a deadlock in the system. identify the sequence that does not cause a deadlock.