Given the following information about resources in a system:

There are two classes of resources labeled R1 and R2. Each resource has two instances. There are four processes, labeled P1 to P4. Here are some examples of resources allocated to processes:

An instance of R1 held by P2, another instance of R1 held by P3, an instance of R2 held by P1, another instance of R2 held by P4, Some processes require additional resources such as:

P1 requests an instance of R1 P3 requests an R2 instance

a. Plot the resource allocation graph for this system.

b. Is it possible for a lock situation to occur in this case? Why or why not?

c. Give a possible process execution sequence that will not cause deadlock.