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Java RMI [3 points] The Java RMI system consists of three main layers: the stub/skeleton layer, the remote reference layer, and the transport layer. For each layer, give one succinct bullet explaining each of these layers.

Lamport’s ME Algorithm The context for this question is the same as the previous question. [6 points] Consider a distributed system with 3 nodes (P1, P2, P3) implementing Lamport’s mutual exclusion algorithm, as shown in the Figure. The boxes represent requests made by a node at a particular timestamp. For example, P1,4 represents a request for the resource made by node P1 at timestamp 4. The red arrows represent requests, and green arrows represent the corresponding acknowledgment messages. c) [2 points] Suggest a simple method to prevent the algorithm from failing due to message loss.

Lamport’s ME Algorithm [6 points] Consider a distributed system with 3 nodes (P1, P2, P3) implementing Lamport’s mutual exclusion algorithm, as shown in the Figure. The boxes represent requests made by a node at a particular timestamp. For example, P1,4 represents a request for the resource made by node P1 at timestamp 4. The red arrows represent requests, and green arrows represent the corresponding acknowledgment messages. a) [2 points] Which node gets access to the resource first and at which point in time (T1-T7)? Justify your answer to get any credit.

Distributed Shared Memory [8 points] In Treadmarks DSM system the following critical section is executed at a node N1: Lock(L1); // Assume X is the only page that been modified up to this point by prior acquirers of L1     Write to Page X;      // Assume that the page is not present at this node;      // Assume that there are three diff files for page X      // named Xd2, Xd3, and Xd4 in nodes N2, N3, and N4      // respectively.      // Assume the sync causality for the lock L1 is       // N3 -> N2 -> N1 (i.e, this is the order of lock     // acquisition).Unlock (L1); a) [2 points] What actions would be carried out by Treadmarks at the point of lock acquisition? Why?

Match each vertebrate group to the innovation they’re famous for!

Place these events in the correct evolutionary order, earliest to most recent:

Which of the following statements correctly describes a major mammal group?

Which statement best captures what biologists infer about the origin of animals?

Slowness of motor movement is referred to as:

Which condition listed below occurs more often in women (compared to men)?